Choosing the Right Landscape Plants A3864 Factors
Choosing Plants 2:Layout 1 8/28/08 3:28 PM Page a
A3864
Choosing the right landscapefactors to plants consider
Laura G. Jull Choosing Plants 2:Layout 1 8/28/08 3:28 PM Page b
c o n t e n t s
Climatic considerations 1
The plant’s function in the landscape 4
Size, form, and growth rate considerations 7
Ornamental considerations 10
Cultural considerations 14
Native habitat and invasiveness 1 8
Selecting high-quality nursery stock 1 9 Properly placed and R e f e r e n c e s 2 0 cared for landscape For more information 2 0 plants can increase the List of scientific names 20 value of real estate.
However, poor plant
choices can become a
maintenance problem and
create an unsightly
landscape. Mismatched
cultural requirements,
improper planting (too
deep), and vandalism
account for more tree
and shrub deaths than
all insect and disease-
related deaths combined.
Always strive to plant
the right plant in the
right place. Choosing Plants 2:Layout 1 8/28/08 3:28 PM Page 1
What plants are adapted to my climate? ? Plant selection is one of the most Urban areas usually are slightly warmer than rural areas due to the “heat island” important decisions a gardener, landscaper, effect created by heat from sewers and furnaces. Heat that is trapped and or designer makes when landscaping. sheltered by buildings and streets also contributes to this effect. In addition, Questions to consider are: These questions, along with the selection unique microclimates can be created at I What plants are adapted to my climate? criteria discussed in this publication, specific sites. For example, trees planted should provide the basis for your I How is the plant to be used in the close to black asphalt pavement will have landscape plant choices. Choosing the landscape? warmer conditions in summer and will proper plants for a landscape help to probably need more water than those I What are the space considerations of ensure the plant has the best chance for same plants planted in the middle of a the site? healthy growth, development, and long- park area. Some areas also may be subject I How big does the plant get and how term survival. to early and late frosts, particularly sites at fast does it grow? higher elevations and those in low areas or I Does the plant have showy flowers and frost pockets. In light of these differences, fruit? two very important climatic adaptability criteria to consider when choosing plants I Is the foliage colorful during the Climatic are USDA Cold Hardiness Zones and growing season or in autumn? considerationsClimate American Horticultural Society (AHS) Heat I Does the plant have interesting bark or Climate is perhaps the most important Zones. branches? factor when choosing landscape plants. The ability of a plant to adapt to a given I What cultural requirements does it climate is referred to as hardiness; it need? involves tolerance to both low and high I Is the plant susceptible to insects or temperatures. It is very important to use diseases? species that can survive the temperature I Is the plant sensitive to air pollution or extremes of your location. If the plant is deicing salts? not tolerant to your particular winter I What type of landscape maintenance conditions, a perennial will perform like an am I willing to provide? annual and die over winter. I Are there any regulations or local ordinances preventing me from sunrise forsythia planting? I What existing vegetation exists in the area? Are there any invasive plants? I How do I know if I am purchasing high- quality nursery stock?
Note: This publication identifies plants by their common names;if you’re interested in learning more about a given plant, you may wish to refer to the list on pages 20 and 21 for the full scientific name to ensure that you’re looking up the same plant.
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choosing the right landscape plants Cold hardiness This subdivision is critical for estimating Heat tolerance USDA cold hardiness zones are based on cold hardiness of some woody plants. American Horticultural Society Heat Zones the range of average annual minimum When in doubt as to whether you are in are based on average annual days that are winter temperatures. Lower zone numbers the “a” or “b” part of a cold hardiness zone, above 86°F.Wisconsin has four heat zones: indicate colder climates; higher numbers it is better to err on the side of plants that zone 2 (northeastern Wisconsin along the indicate warmer climates.Wisconsin has are hardy to the colder “a” zone.Winter Upper Peninsula of Michigan border), three cold hardiness zones: zone 3 hardiness is crucial in plant selection, zone 3 (north central Wisconsin and Door (northern Wisconsin), zone 4 (central and health, and survival. Lack of hardiness can County), zone 4 (most of western, central, southwestern Wisconsin), and zone 5 lead to dieback, decline in plant health, and eastern Wisconsin), and zone 5 (southeastern Wisconsin).The hardiness death of flower buds, or damage or (extreme southern and western Wisconsin). zones are further divided into two sub- destruction to the entire plant. For Heat zones are particularly important in zones of either “a“ (the colder half of the example, the flower buds of border the southern and western U.S., but also are hardiness zone) or “b” (the warmer). For forsythia are not cold hardy to zone 4b but important in the northern U.S. For example, the hardiness zone in Portage, the flower buds of Sunrise forsythia are example, paper birch and pagoda Wisconsin, is zone 4b while Stevens Point, cold hardy; therefore, choosing cultivars dogwood, species preferring heat zones Wisconsin, is in zone 4a.This means that a and species that are hardy to your area is below 5, are not suitable in some parts of zone 4 hardy plant is cold hardy to –20°F to crucial. Many horticultural reference and southern Wisconsin, especially in urban –30°F with further division of this zone into gardening books and plant labels now list areas, and will not thrive in those locations. zone 4a (hardy –25°F to –30°F) or zone 4b the subdivision of the zones (“a” and “b”). They are cool, woodland species native to (hardy –20°F to –25°F). When in doubt, ask a local nursery or northern Wisconsin.They become garden center for appropriate plants for susceptible to insects, such as bronze birch your area or contact your local county borer (birch) or golden canker (dogwood) Extension office for further information. when grown in the poor, dry soils and high temperature extremes common in urban usda cold hardiness zones and some suburban environments. Average annual minimum winter temperatures
3a –35° to –40°F 3b –30° to –35°F 4a –25° to –30°F
4b –20° to –25°F
–15° to –20°F
5b –10° to –15°F
american horticultural society plant heat zone map Average number of days per year above 86°F
2 1–7 days 3 8–14 days
4 15–30 days
5 31–45 days
6 46–60 days
7 61–90 days Reproduced with permission of the American Horticultural Society (www.ahs.org).
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High temperatures are important because they affect the supply of carbohydrates (sugars) plants manufacture for themselves during the day by photosynthesis. Plants use stored carbohydrates to produce new leaves, shoots, roots, and fruit. Sugars are also involved in several physiological processes, and generate important plant pigments, such as anthocyanin (red, purple, and blue pigments).When plants with poor heat tolerance are grown in regions that routinely experience high summer day and night temperatures, they often eastern redbud “burn up” much of their supply of stored carbohydrates during the evening hours. Provenance In contrast, the more northern provenances have greater cold hardiness These conditions occur not only in warmer (geographic seed source) and should be chosen for use in the Upper areas of the U.S., but can also take place in One other important adaptability criteria Midwest when propagating or growing urban environments, containers, and city to consider when choosing plants is species such as eastern redbud.This may boulevards. Plants like the purple-leaf provenance. Provenance refers to the also hold true for non-native, exotic beech offer an example.The tree has geographic origin of the seed. Provenance species. purple leaves during the cooler parts of is not an issue for vegetatively propagated spring and early summer, but when (via cuttings, budding/grafting, tissue excessively high temperatures occur in culture, layering) species and cultivars, but Trees best grown from warmer heat zones of 6 and higher, it is very important for some native and exotic species that have a wide, native northern seed sources respiration rates at night increase and Scientific name Common name there are not enough carbohydrates geographic range and are primarily Acer rubrum Red maple (sugars) left over for purple pigment to propagated by seed. develop.The leaves can fade to a greenish- You may not know whether a nursery or Asimina triloba Pawpaw purple.This does not harm the plant but garden center has obtained seed- defeats the purpose of growing this propagated plant material from a northern Betula nigra River birch purple-leaved tree in the first place. seed source, but you can try asking. For Carpinus caroliniana American hornbeam example, eastern redbud is native from Some trees will die due to excessively high or musclewood temperatures. Heat also increases New Jersey to northern Florida, and west a susceptibility to insects and diseases, to Illinois and northern Mexico. Some Cercis canadensis Eastern redbud growers have been known to collect seed especially wood-boring insects and root Cornus florida Flowering dogwood rots. In these microclimates, the stored or buy nursery stock of eastern redbud carbohydrates are used for nighttime trees growing in southern U.S. locations, Fagus grandifolia American beech respiration, leaving little for defense such as Tennessee, and sell them in Liriodendron tulipifera Tuliptree, tulip-poplar against pests. Generally, for most northern markets.These seed-propagated, southern provenances of eastern redbud residential locations, you do not have to Morella (formerly Northern bayberry are less cold hardy and require a shorter worry about heat tolerance unless a Myrica) pensylvanica species specifically requires a cooler or dormancy to break bud. Consequently, shady environment with adequate plants grown from southern seed sources Nyssa sylvatica Black gum, tupelo moisture. are prone to winter damage and may break bud early in spring, making them Pinus ponderosa Ponderosa pine vulnerable to frost damage. Pseudotsuga menziesii Douglas-fir var. glauca
Quercus spp. Oaks (most)
Sassafras albidum Sassafras
Taxodium distichum Baldcypress
aRedbuds sold as “Columbus strain” or “Minnesota strain” come from a northern provenance.
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How is the plant to be used ? in the landscape?
The plant’s function in thehe functional landscape use of a plant in the Street trees landscape is a central Trees that are to be planted along a street consideration when making plant should tolerate heat, drought, poor choices. Plants can function in multiple drainage and aeration, soil compaction, Tways in the landscape; this can make your low fertility, high pH, deicing salts, and air choice even more difficult. Pay attention to pollution.They should also be cold hardy i v o r y s i l k the particular features of different plants; to your area and resist pests. Street trees j a p a n e s e these may give you ideas about where in often suffer greatly due to lack of water t r e e l i l a c the landscape they might best be put to and restricted rooting area; hence, use. Here are some guidelines. selection of an appropriate species is Screens important for the tree’s growth and Plants can be used to eliminate an Shade trees survival. Maybe the best choice is not to undesirable view, smell, block noise, or trap How dense do you want your shade to be? plant a tree, but to select herbaceous dust and debris from roads.They also Trees that produce dense shade, such as perennials or annuals. outline space and create outdoor spaces or maples and oaks, should be planted where “rooms” in the landscape and provide When planting a street tree, remember to there is enough space, as well as sunlight. privacy. Usually, a single species with a “look up”for power lines and avoid planting These species work well on the southeast, dense habit is planted in a row, preferably species that get large at maturity (taller southwest, and west sides of buildings and evergreens with low branches. Sometimes than 30 ft.) near utilities. For example, homes by providing cool shade in summer, berms (elongated mounds) are used to many maples, oaks, honeylocusts, and which can significantly lower your cooling screen views.The plants can be sheared lindens get too tall to plant near power costs. Deciduous trees drop their leaves in into a tall hedge (see next page under lines. However, if power lines are not a autumn which allows for the low, winter hedge), or allowed to spread naturally. problem and sufficient rooting area is sun to shine through your windows, Most evergreen trees such as pines, spruce, provided, many of these trees make good bringing heat and light into the home. fir, Douglas-fir, eastern hemlock, northern street tree choices. Some oaks can make white-cedar, and eastern red-cedar look good street trees if the acorn litter in best if allowed to grow naturally and can autumn is not a serious issue. Good choices serve as very effective screening plants in for street trees Specimens the landscape. Scientific name Common name A specimen plant can stand alone in the Short trees (suitable near power lines) landscape and serve as a focal point.The plant’s ornamental Malus spp. Flowering crabapples characteristics draw Syringa reticulata Japanese tree lilac your attention to it. It may have a unique Tall trees (not suitable near power lines) form or texture, showy foliage, flowers, fruit, or Acer miyabei ‘Morton’ State Street® interesting bark or Miyabe maple branching. A specimen Acer x freemanii Freeman maple plant can be combined with other plants in compact american Ginkgo (male cultivars) Ginkgo biloba mixed shrub or cranberrybush viburnum Gleditsia triacanthos Honeylocust (male herbaceous perennial var. inermis cultivars) borders. Many small, ornamental trees are specimen plants such as flowering Quercus muehlenbergii Chinkapin oak crabapple and Japanese tree lilac. Taxodium distichum Baldcypress
Tilia spp. Lindens
Ulmus spp. Elms (hybrids)
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Hedges, barriers, a n d s c r e e n s Scientific name Common name
Screens (best if allowed to grow naturally) Windbreaks Do not shear ornamental flowering shrubs Abies spp. Firs Plants can serve to reduce the force of the such as forsythia, lilacs, dogwoods, or wind.Windbreaks are often made up of spirea into formal hedges, as you will be Juniperus virginiana Eastern red-cedar removing flower buds. Flower buds are one species planted in a single row, or Picea spp. Spruces multiple species planted in several rows. commonly formed in mid to late summer Evergreens are a better choice for for the following spring season.These and Pinus spp. Pines windbreaks as they retain their leaves in other deciduous or evergreen species can Pseudotsuga menziesii Douglas-fir winter when cold winds are at their worst. be used as informal hedges where their var. glauca Evergreens also serve as a screen to block natural shape is retained and they are not views (see above under screen). Evergreen sheared. Avoid the use of tallhedge Thuja occidentalis Arborvitae, white-cedar windbreaks can provide cover for wildlife, buckthorn and Tatarian honeysuckle as particularly in winter. hedge plants. Both species are highly Tsuga canadensis Eastern hemlock invasive in woodlands, prairies, and Hedges wetlands. Formal hedges (tolerates shearing) A hedge is a living green fence usually Buxus spp. Boxwoods consisting of one species, often planted Barriers close together in a single or double row A barrier plant is typically a defensive Taxus spp. Yews hedge to keep objects away and deter foot with alternate spacing. Hedges help define Thuja occidentalis Arborvitae, white-cedar or divide portions of your property or traffic. Barrier plants usually have thorns or direct pedestrian traffic.They can be are quite twiggy, with sharp branches. Tsuga canadensis Eastern hemlock ornamental or defensive (barrier) and can Shrub roses, barberry, and hawthorn are be trimmed to produce a tight, formal some examples of plants that make Informal hedges (do not shear) appearance or allowed to grow naturally, effective barriers. Cornus spp. Dogwoods creating an informal effect. Evergreens used as hedge plants can also serve as a Forsythia spp. Forsythias screen. Spiraea spp. Spireas For formal hedges, choose evergreen Syringa spp. Lilacs species that can tolerate shearing and have dormant buds along the stem that Barriers can break and re-grow. Such species Berberis spp. Barberries include boxwood, yews, arborvitae or white-cedar, or eastern hemlock. Avoid use Crataegus spp. Hawthorns of junipers, spruces, and most pines in tightly clipped hedges as these plants Rosa spp. Shrub roses grow mainly from the tips of branches where the buds are formed.Yearly, repeated trimming of these shrubs to the same point will result in dead tissue, barrier (shrub rose) unsightly plants, and poor performance.
i n f o r m a l h e d g e ( y e w )
f o r m a l h e d g e ( y e w )
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choosing the right landscape plants Vine Vines climb by special adaptations such as tendrils, tendrils with adhesive discs at the tips, rootlets (adventitious roots), or by twining around a structure or fence.Vines create the “walls” and “ceilings” of the landscape as they can be used on walls, trellises, or allowed to grow over arbors or pergolas. Some vines, such as Oriental b o r d e r bittersweet and English ivy, are invasive (alpine currant) and choke out trees and other plants as they climb over them. Avoid planting these Borders Masses species. American bittersweet is a good Shrub borders are often planted along the A mass planting consists of a number of alternative, native, non-invasive vine that perimeter of a house or in landscape beds plants, either the same or a combination of can be used instead of Oriental that define boundaries; for example, the species, planted close together that often bittersweet. Some vines have beautiful line between your yard and your screen a view. If they are tall enough, flowers such as Kentucky wisteria and neighbor’s.You can create a mixed border masses can provide a windbreak. Both sweet autumn clematis. using both woody and herbaceous evergreens and flowering shrubs can be Container plants perennials. used in masses. Make sure you do not Some shrubs and a few, smaller trees can crowd the plants together as plants placed be grown outdoors in insulated containers, Edging too close together will shed their inner provided they receive enough light with Edging refers to planting of low-growing leaves and branches to compensate for consistent watering, adequate drainage, species along the margin of a landscape reduced light levels. bed, helping to define a border. It can and pruning during the growing season. comprise one or more species and the Groundcover Containers can be used in tight spaces, on plants typically grow less than 3 feet tall. A groundcover is a flat or trailing plant that patios, decks, or in areas where a splash of Boxwood and Crimson Pygmy Japanese spreads along the ground. It creates the color is needed. A few trees that can be barberry are commonly used for edging. “floor” of the landscape and can help grown in containers include Cinderella®, prevent erosion and stabilize slopes or Firebird®, and Tina crabapples. Foundation banks. Some groundcovers can tolerate Foundation plants can be individual plants deep shade like Japanese pachysandra, or combinations of plants placed next to while others require full sun like junipers. homes and buildings to soften the Groundcovers are usually evergreen, but structure.To allow access to windows and there are some flowering groundcovers clearance near awnings, plants selected as such as sweet woodruff and creeping foundation plants usually grow lower than phlox. 6 feet tall. Plant taller or wide-spreading trees and shrubs away from windows and entranceways to allow people to pass.
f o u n d a t i o n ( s a y b r o o k gold juniper)
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What are the space considerations of the site? ?
Size, form, and growth rate hen making your plant considerationsselection, it’s important to think about how tall and wideW the plant will ultimately become and whether it will still fit your space years later.
Size Trees and shrubs typically are planted when young.Take care to consider how their growth will impact the landscape in the future.Too often, the mature height and width of tree and shrub branches and roots are not taken into consideration. Utility lines, both above and below ground, sewers, light posts, sidewalks, roads, and other structures should be considered as you decide how large a tree or shrub to plant. Power and construction companies will be forced to prune back your plants if they are too large and become an obstruction. Also, remember vehicular and pedestrian traffic. More maintenance pruning will be required to prevent How big does the plant get and obstruction of view and unsafe conditions how fast does it grow? such as thorny or prickly foliage that ? extends over the street or sidewalk, messy fruit that creates slippery walkways, and Form Growth rate spreading branches that prevent drivers You need to be aware of the plant’s form A plant’s genetic makeup, the length of the from seeing traffic. and branching characteristics. (Common growing season, and the attention given to plant forms are pictured on pages 8 and 9.) the plant’s culture will determine how Avoid crowding plants together or Form and branching refers to the plant’s quickly a tree or shrub grows. A fast- planting trees too close to buildings, even overall size, shape, and outline. For narrow growing tree may be important when though this may be visually appealing at spaces, choose plants that have a columnar planting for shade or screening. However, first.You will eventually have to remove or or fastigiate form, with larger, vase-shaped some fast-growing species have weak relocate plants that get too big for the or spreading trees in bigger areas. Most wood, poor branch attachment, and are area. Large trees planted too close to a trees are pyramidal when young and prone to storm breakage. Silver maples, building can cause infrastructure or become rounded or open with age. In willows, and Siberian elm are subject to foundation damage from the roots and general, pick trees that have a balanced this problem and need more frequent branches and become a liability. and attractive branch pattern. Look for pruning. Slow-growing trees and shrubs wide crotch angles such as ginkgo and Koreanspice viburnum between the branches and may be beneficial near streets and homes, the main trunk of the tree because of fewer maintenance (pruning) to avoid large limb requirements. breakage later. Don’t forget to consider the size of the root system of the mature plant. Roots often require more space than most people think.
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different plant forms
a r c h i n g : Branches on tree or shrub c o n i c a l : Geometric cone-shape e r e c t : Upright, with tall, straight arch over, creating a fountain or (like an upside-down ice cream cone), stems; can also refer to columnar or cascading look. common in evergreens. fastigiate forms. Usually used to describe shrubs.
c l i m b i n g : Stems of a plant grow fastigiate: Narrow, upright upwards along a fence, trellis, wall, or branching with closely arranged other structure; common in vines. creeping or trailing: branches. Growth is less tight than Branches and foliage lay close to the columnar. ground or trail over walls or boulders; common in groundcovers.
c l u m p : Main branches or multiple trunks of a tree arise from the base of the plant. Common in ornamental trees d e n s e : More compact form than that have showy bark; nurseries typical; branches and foliage are close intentionally grow them this way. together, unable to see through. h o r i z o n t a l : Branches are parallel to the ground, creating a wide- spreading, flat-topped look.
d w a r f : Miniature form, much smaller than usual; common in conifers. i r r e g u l a r : No distinct shape, but form can be picturesque.
c o l u m n a r : Branches are closely arranged on the stem creating a narrow, vertical habit. Narrower growth than fastigiate.
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m o u n d e d : Low, rounded form, p y r a m i d a l : Somewhat triangular u p r i g h t : Branches tend to go close to ground. in outline. Base is widest part and upwards and are often rigid. narrows at top; formal looking.
vase-shaped: Upper part of a rounded or globular: tree canopy or shrub outline is shaped o p e n : Branches are far enough apart Curved outline; top of plant resembles like a V. to allow air and light through—you can the upper half of a circle, common in see through it. trees.
w e e p i n g : Stems of a tree or shrub gracefully arch or bend over toward the ground. Often grafted. s p r e a d i n g : Branches spread upward and outward; common in trees or larger shrubs.
o v a l : Egg-shaped; lower and upper portions of plant are narrower than the middle.
s u c k e r i n g : Multiple stems originate below ground from the roots, resulting in new shoots, common in shrubs.
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Does the plant have showy ? flowers and fruit?
Ornamentaln terms of overall ornamental impact, considerationsThe duration of it’s generally considered best to bloom varies choose plants with year-round interest. dramatically While a plant’s flowers are often the main with each plant. reasonI why people select a particular Nevertheless, plant, also look at features that will be most flowers present at other times of the year. only last one to two weeks and Flowers for the rest of The time, duration, color, fragrance, and the year, we showiness of flowers are important must depend aesthetic features. Most woody plants on other flower in the spring, a few species flower in ornamental the summer, and even fewer flower in the features such as autumn or winter.You can produce a fruit, leaves, fall leonard messel magnolia wonderful effect in the landscape when color, or bark you choose a variety of plants with and branching, which are visually The primary consideration with flowers is: different flowering times, so that appealing for much longer periods. Some Are they large and showy or small, and something is nearly always in bloom. Many shrubs have longer-lasting flowers such as best seen up close? Do they really make an flowers bloom in spring, but summersweet shrub roses, butterfly bush, potentilla, impact in the landscape? Maybe individual clethra, hydrangeas, and clematis are Japanese spirea, and panicle hydrangea. flowers are not particularly showy but species that flower in summer. Many shrub Remember, flower displays can be cut when many are produced or occur in roses and common witchhazel flower into short if there is a frost, drought, excessively clusters before the leaves emerge, the autumn. warm temperatures, high winds, or heavy impact is significant.What color are the rains. flowers? Most are white, pink, or mauve, It is also a great idea to place plants with with yellow and orange being uncommon Flowering plants fragrant flowers near entranceways and flower colors in temperate woody plants. Plants with yellow flowers include Scientific name Common name windows. Some in this category include shrub roses, lilacs, magnolias, and the forsythias, corneliancherry dogwood, and Fragrant autumn blooming vine, sweet autumn Butterflies magnolia. Make sure the flower Clematis terniflora Sweet autumn clematis clematis. Fragrance is related to color does not clash with the building or temperature and humidity; high house color or with another plant in bloom Magnolia spp. Magnolias temperatures and humidity increase at the same time. Rosa spp. Shrub roses fragrance while cooler temperatures or rain affect it negatively. Syringa spp. Lilacs
Tilia spp. Lindens
Viburnum carlesii Koreanspice viburnum
Long-lasting Buddleja davidii Butterfly bush
Hamamelis virginiana Common witchhazel
Hydrangea paniculata Panicle hydrangea
Potentilla fruticosa Potentilla
Rosa spp. Shrub roses
Spiraea japonica Japanese spirea
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Selecting for fruit Scientific name Common name Showy Aronia spp. Chokeberries
Celastrus scandens American bittersweet
Ilex verticillata Winterberry
Viburnum spp. Viburnums (some) serviceberry Attractive to wildlife Amelanchier spp. Serviceberries Fruit How visible are the fruit? Red is one of the best colors to draw attention because it Fruit often last longer than flowers and are Carya spp. Hickories a particularly important ornamental attracts not only people but also birds consideration. Fruiting mostly occurs in looking for food. Other colors that occur in Corylus spp. Hazelnuts late summer to autumn.The ornamental fruit are white, yellow, orange, blue, black, Crataegus spp. Hawthorns characteristics of fruit can be positive or purple, pink, and bicolor. Are fruit borne negative and are influenced by numerous singly or in clusters, which tend to be Fagus spp. Beeches factors. Some fruits are quite unsightly and showier? Does the foliage hide the fruit? spp. Flowering crabapples create a tremendous litter problem; for Does it drop early? Some shrubs have Malus outstanding displays of fruit such as red example, black walnut, female thornless Quercus spp. Oaks honeylocust, and Hopa crabapple. Others, and black chokeberries, some viburnums, such as female ginkgo trees, have a very winterberry, and the vine, American Viburnum spp. Viburnums (some) foul odor.The brightly colored fruit of bittersweet. Edible some ornamental crabapples such as Red The edibility of fruit is an important Jewel®, Harvest Gold®, and Firebird® are consideration when choosing plants for Amelanchier spp. Serviceberries important for winter interest, but it is best public areas. Poisonous plants, such as Cornus mas Corneliancherry to find varieties, such as the ones listed, horsechestnuts and buckeyes, snowberry, dogwood with small, persistent fruit that won’t make burningbush, and the vine, American a mess on sidewalks.With many plants, the bittersweet, are not appropriate for Corylus spp. Hazelnuts fruit is a positive ornamental feature and playgrounds or places with children close factors such as color, showiness, and by, while plants that produce edible fruit Poisonous attraction for wildlife should also be such as serviceberry, corneliancherry Aesculus spp. Horsechestnuts considered. dogwood, and hazelnuts make wonderful and buckeyes Many people enjoy watching wildlife that additions to your yard. Celastrus scandens American bittersweet feeds on fruit. Plants with fleshy fruit that A final consideration regarding fruit is the attract wildlife include crabapples, plant’s pollination requirements.You may Euonymus alatus Burningbush hawthorns, serviceberry, and most need pollination by another cultivar of the viburnums. Dry nut fruit can also attract same species to get good fruit set, as is the Symphoricarpos albus Snowberry birds and other mammals. Species that case with viburnums. Or the plant may be Taxus spp. Yews produce nut fruit are usually large trees dioecious, meaning it has separate male such as oaks, beeches, and hickories.There and female flowers located on two are also a few shrubs that produce nut fruit different plants. Dioecious plants require a thornless honeylocust, and Kentucky such as hazelnuts. However, fruit male and female plant located close to coffeetree female trees produce messy sometimes attracts unwanted visitors, such each other to produce fruit. Examples fruit, while the cultivars Autumn Gold, as deer, that not only feed on the available include winterberry, and northern Skycole (Skyline®), fruit but on other plants as well— bayberry.You may and Espresso are defoliating, damaging, or destroying them. not want to grow the o a k fruitless, male For more information on deer-resistant female fruit of a cultivars of ginkgo, plants, see the UW-Extension publication particular dioecious thornless Plants Not Favored by Deer (A3727). species due to its honeylocust, and smell or litter mess. Kentucky coffeetree, Planting a male respectively. cultivar can overcome these problems. Ginkgo,
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Is the foliage colorful during ? the growing season or in autumn? Foliage as Carol Mackie The foliage of ornamental plants exhibits Daphne, many characteristics to consider when variegated making choices for a landscape. Most Tatarian dogwood, leaves are green, but there are different and Japanese shades such as blue-green, or forest green. dappled willow As leaves emerge, they may be a different have variegated color than the mature leaves. Some plants leaves; that is, s u g a r m a p l e have purple leaves throughout the leaves with two growing season and include Black Lace™ different colors What about fall color? Fall color is an elderberry, Crimson King and Royal Red such as white and green or yellow and important consideration given its Norway maples, and Diabolo® and Summer green.Variegated leaves provide a nice spectacular contribution to the landscape. Wine® eastern ninebark. A few species such splash of color and serve as a focal point in Some plants have poor or nonexistent fall the landscape. color (yellowish-brown), while others are Don’t forget evergreens—they are not just plants with interesting vibrant yellow, orange, red, or purple.Trees f o l i a g e green. Some evergreens, such as Rainbow’s with outstanding fall color include Autumn End dwarf spruce, produce yellow new ® Scientific name Common name Blaze Freeman maple, sugar maple, growth in spring before they turn green. ginkgo, and apple serviceberry.There are Yellow to gold Some evergreens stay yellow throughout many different shrubs with excellent fall Chamaecyparis pisifera Golden Mop threadleaf the year, such as Golden Mop threadleaf color including red chokeberry, fothergillas, ® ‘Golden Mop’ falsecypress falsecypress and Gold Coast juniper. and sumacs.Virginia creeper and Boston Others have blue needles all year, such as ivy are vines with spectacular fall color. For Juniperus x pfitzeriana Gold Coast® juniper concolor or white fir, or blue spruce. Still more information on plants with showy fall ‘Aurea Improved’ others have a mixture of blue and green color, see UW-Extension publication Picea glauca Rainbow’s End needles such as Swiss stone pine or Selecting Woody Landscape Plants for Fall ‘Rainbow’s End’ dwarf spruce Sander’s Blue dwarf spruce. Color: An Illustrated Guide (A3837). What is the texture of the foliage? Coarse- Thuja occidentalis Sunkist,Yellow Ribbon textured, large foliage on trees allows little ‘Sunkist’,‘Yellow Ribbon’ arborvitae light to penetrate, which inhibits turf growth underneath. Fine-textured foliage Blue (smaller or lacy leaves) on trees allows for Abies concolor Concolor, white fir filtered light shade.Thornless honeylocust, Kentucky coffeetree, and katsuratree Picea glauca Sander’s Blue provide filtered shade, allowing turfgrass ‘Sander’s Blue’ dwarf spruce to grow better than if grown under trees Purple with dense shade. Foliage may also be glossy, dull, smooth, fuzzy, prickly, rough, Acer platanoides ‘Crimson Crimson King, Royal wrinkled, or feathery. Contrast between the King’,‘Royal Red’ Red Norway maples s a n d e r ’ s foliage and the flowers, fruit, bark, or stems b l u e d w a r f Physocarpus opulifolius Diabolo®, Summer Wine® is often one of a plant’s best features. s p r u c e ‘Monlo’,‘Seward’ eastern ninebark Foliage, like some flowers, may be aromatic, especially when rubbed or Sambucus nigra ‘Eva’ Black Lace™ elderberry pruned. Everyone is familiar with fragrant, culinary herbs, such as rosemary, basil, or Variegated thyme, but there are some woody plants Cornus alba Variegated Tatarian with aromatic foliage such as Russian-sage, ‘Argenteo-marginata’ dogwood northern bayberry, arborvitae or eastern Daphne x burkwoodii Carol Mackie Daphne white-cedar or fir.You may only need to ‘Carol Mackie’ brush against these shrubs to notice their aroma, and they are particularly effective Salix integra Japanese dappled when planted near walkways, decks, or ‘Hakuro Nishiki’ willow patios.
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Does the plant have interesting ? bark or branches? A few shrubs and trees have thorns, spines, Bark and branching plants with excellent Many plants have interesting, ornamental or prickles that act as a barrier, preventing f a l l c o l o r bark.The textures and colors contribute unwanted visitors from getting in or out of Scientific name Common name considerable visual appeal and, in some the landscape. Examples include Japanese ® plants, are the primary attraction. barberry, shrub roses, flowering quince, Acer x freemanii Autumn Blaze Deciduous plants are devoid of leaves for and hawthorns. Use caution when planting ‘Jeffersred’ Freeman maple these species near entranceways, patios, or 5–6 months during the dormant season, so Acer saccharum Sugar maple features such as the bark and branches are decks where sharp projections may injure particularly important for creating winter people as they pass by. Amelanchier x grandiflora Apple serviceberry interest.Trees with very showy bark Aronia arbutifolia Red chokeberry include three-flowered maple, paper birch, and Amur chokecherry. Fothergilla spp. Fothergillas Branches can also be ornamental, offering Ginkgo biloba Ginkgo varied colors and textures. Shrubs that have colorful twigs, especially in winter, Hamamelis virginiana Common witchhazel include cultivars of red- and yellow-twig Nyssa sylvatica Black gum, tupelo dogwoods, coral bark willow, and the vine, climbing hydrangea. Some plants’ twig Rhus spp. Sumacs color is not colorful, but their unique winged or twisted branching provides interest in winter. Some plants in this category include burningbush or winged Plants with interesting euonymus, Harry Lauder’s walkingstick, bark or branches and curly willow. Scientific name Common name
Showy bark Acer triflorum Three-flowered maple w i n t e r k i n g h a w t h o r n Betula papyrifera Paper birch
Crataegus viridis Winter King hawthorn ‘Winter King’
Prunus maackii Amur chokecherry
Colorful twigs Cornus stolonifera Redtwig and yellowtwig dogwoods
Hydrangea petiolaris Climbing hydrangea (vine)
Salix alba ‘Britzensis’ Coral bark willow
Unique branching pattern Euonymus alatus Burningbush, winged euonymus
Corylus avellana Harry Lauder’s ‘Contorta’ walkingstick
Salix matsudana Curly willow ‘Tortuosa’
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What cultural requirements ? does it need?
Culturaloil, moisture, sunlight, considerations wind, pest Soil texture is the percentage of susceptibility, air pollution, sand, silt, and clay in a soil. Soil texture is deicing salt and urban tolerance, very difficult to change. Soil texture maintenance considerations, and black influences soil fertility, drainage, and Swalnut toxicity are all critically important aeration of soils. In general, a heavy clay but often overlooked during plant soil has poor aeration and drainage, but selection. If cultural conditions are less can be high in fertility. Sandy soil than optimum for a particular species, it is typically has good aeration and drainage, best to select either another site or species but poor structure, fertility, and water chlorosis on better suited to that specific location. retention. Loamy soil, which has a p i n o a k Matching your plant choices to their balanced blend of sand, silt, and clay, has cultural requirements helps to ensure the good structure, fertility, aeration, Loss of soil structure, caused by plant has the best chance for healthy drainage, and water retention. compaction, reduces water infiltration and growth, development, and long-term Unfortunately, this situation rarely occurs drainage, decreases aeration levels survival. in urban and suburban soils. required for root growth, and makes it Soil Do not attempt to improve a heavy clay more difficult for roots to penetrate the Soil adaptability factors to consider include soil by adding sand; the result will be ground. Poor aeration and drainage in soils texture, structure and compaction, pH and “cement.” Instead, add organic material, is evident where there is standing water, fertility, and temperature. Choose plants such as sphagnum peat, leaf compost, pine slow drainage, and a hard soil surface that that are tolerant, especially to your soil bark, or other organic compost. Many resembles baked clay. Soil compaction is a texture and pH. A soil test taken before plants tolerate some amount of clay in the major cause of tree decline, poor growth, you choose your plants will determine soil, but there are few plant choices for dry, and eventual plant death in urban and your soil texture, pH, and fertility levels and sandy soils. Some species that can adapt to suburban areas. help in making appropriate plant these conditions are northern bayberry, In urban conditions, it is vitally important selections. common hackberry, shagbark hickory, to choose plants that tolerate compacted creeping juniper, black oak, red pine, soils, or to improve the soil structure. If the rugosa rose, and yucca. soil is heavily compacted and/or poorly Plants for dry, Soil structure and drained (standing water for more than an s a n d y s o i l s compaction is a great concern in hour following rainfall), consider improving Scientific name Common name landscape plantings, particularly in urban drainage before planting by adding loose Carya ovata Shagbark hickory and suburban environments. Soil structure organic matter (peat moss, composted leaf refers to the soil’s ability to form mulch, pine bark, or compost) to raise the Celtis occidentalis Common hackberry aggregates (solid particles) of different planting area.This helps roots become Juniperus horizontalis Creeping juniper sizes, both large and small.These established in well-oxygenated soils. aggregates form under natural conditions Rototillers can be used to loosen up the Juniperus virginiana Eastern red-cedar over long periods of time. Disturbing or soil prior to planting, but do not rototill soil manipulating the soil reduces or even Morella (formerly Myrica) Northern bayberry directly under established trees; doing so destroys the soil’s structure. Construction is pensylvanica will cut the roots into pieces and lead to a common cause of soil destruction when tree decline. Do not apply topsoil or Pinus resinosa Red pine topsoil is removed and compacted, leaving organic matter directly into the planting high-clay subsoil behind. Compaction may Quercus velutina Black oak area, as this will create an interface also be caused by excessive foot and car between the poorly drained soil and the Rosa rugosa Rugosa rose traffic. well-drained material you added, creating a “bathtub” effect where water stays in the Yucca spp. Yuccas hole and does not drain out into the existing soil.There are some plants that can tolerate heavily compacted soils such as common hackberry, hybrid elms, Kentucky coffeetree, and gray dogwood.
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Plants that tolerate moisture extremes Scientific name Common name
Tolerates dry soils (once established) Soil pH and fertility are also Soil temperature influences root Cornus racemosa Gray dogwood important considerations when choosing growth and the rate of chemical and landscape plants.The pH of a soil is based biological processes.Temperature Cotoneaster spp. Cotoneasters on a range of 0 (very acidic) to 14 (very extremes can dry out and freeze roots. In alkaline) with a neutral pH of 7.0. Most paved or restricted rooting areas or areas Juniperus spp. Junipers woody plants prefer slightly acidic soil with surrounded by concrete or pavement Quercus macrocarpa Bur oak a pH of 5.5–6.5.You can increase the pH by (parking lots, sidewalk cutouts, and addition of lime, though this is rarely containers), soil temperatures may be Tolerates wet soils needed in urban or suburban areas in colder in the winter and warmer in the Cornus stolonifera Redtwig and southern Wisconsin.You can lower the pH summer than those in nearby lawn areas. yellowtwig dogwoods by adding elemental sulfur and organic Adding mulch to the top of the planting matter, but this is a slow process, as natural area will help cool soils in summer, insulate Quercus bicolor Swamp white oak bacteria will need to convert this insoluble roots in winter, and retain moisture sulphur to a form plants can use. throughout the year. Apply mulch 2–4 Salix spp. Willows Nutrient availability is often directly related inches deep and avoid mulch touching the Taxodium distichum Baldcypress to soil pH. Species such as pin oak, red trunk or branches.With regard to maple, river birch, and rugosa rose become containers, they must have drainage and very chlorotic in southeastern Wisconsin be large enough to accommodate the root Other considerations include how much because the pH is too high (alkaline) and system and insulated to help the plant rainfall the site typically receives.When are iron, or manganese in the case of red survive cold winters. Roots die at the dry months and do they occur during maple, is unavailable for root uptake. significantly warmer temperatures than the growing season? If so, a lack of rainfall Chlorosis symptoms occur on leaves when the tops of plants. will significantly affect plant growth and the plants are grown at high pH and development of leaves, flowers, and fruit. Moisture manifest themselves with yellowing leaves Excessive rain can flood areas, decreasing Soil moisture conditions are strongly with the main veins in the leaf remaining available soil oxygen—a requirement for influenced by the previous factors of soil dark green. Choose plants that are tolerant all plants. During winter, snow and ice can texture, structure, temperature, and others to high pH soils if your soil is alkaline. For weigh branches down and cause limbs to such as precipitation patterns and soil more information on chlorosis and how to break.These are serious factors to consider interfaces. Most woody plants need about lower your soil pH, see the UW-Extension when choosing landscape plants. 1 inch of water a week and will need publication Oak and Other Trees Disorder: supplemental irrigation when sufficient Sunlight Chlorosis (A2638). rainfall does not occur. Low soil moisture Since plants require sunlight for growth, Some species, such as rhododendrons and often occurs in sandy soils, during drought, exposure to the sun is a basic azaleas, not only require a slightly acidic to where there are high soil surface environmental consideration when acidic pH, but also fertile soils that are high temperatures, or when there is high selecting plants. Most plants prefer full sun in organic matter and nutrients. Soil deicing salt content in the soil. If your soil to light shade for proper growth and fertility can be improved by adding moisture characteristics are poor (too wet flowering while some tolerate dense shade organic matter such as compost or leaf or too dry) and cannot be improved, be and are often found as understory plants mold, or by using slow or quick-release sure to choose plants that tolerate those in woodlands. Plants requiring full sun fertilizers. A good rule of thumb is that conditions. conditions will need at least 6 hours of before you plant anything, make sure you In general, plants like moist, well-drained direct sunlight per day; partial shade get a soil test to determine pH and soils, but some are drought-tolerant and a tolerant plants require 2–5 hours of direct nutrient levels.You may already have few tolerate wet soils. Some plants that are sunlight per day, particularly in the sufficient phosphorus and potassium in drought-tolerant (once established) mornings, whereas shade-loving plants your soil and addition of more will not be include bur oak, junipers, cotoneasters, and need less than 2 hours of direct sunlight beneficial to plants. gray dogwood.Willows, baldcypress, each day, filtered sunlight, or no direct sun. swamp white oak, and red- or yellow-twig Some plants that tolerate partial to full dogwoods are some of the plants that shade include Annabelle hydrangea, Carol tolerate wet soils. Many of the plants that Mackie daphne, witchhazels, yews, and tolerate wet soil also tolerate poorly eastern hemlock. drained, compacted soils.
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Is the plant sensitive to air ? pollution or deicing salts? Consider the duration and directness of Avoid using sunlight. Do buildings or other trees shade structurally the site? The type of shade in a landscape weak tree can change over time, becoming denser as species like trees and shrubs mature and fill in spaces. willows, Light patterns can also change with the poplars, and seasons and can affect growth patterns. An silver maple, a n n a b e l l e h y d r a n g e a area that is in full sun in summer when the that are prone sun is high in the sky may have partial to storm shade in spring and fall when the sun is at damage. a lower angle.Visiting the site at different These species can cause significant Air pollution times of the day and season will help you damage during storms if planted near Air quality is an important factor for a determine the light patterns and choose a homes or other structures. Use trees that sensitive plant’s growth and survival. Plants species appropriate to those conditions. have strong wood and branch are subject to site, size, and traffic patterns attachments with wide crotch angles (the (for example, exhaust fumes) of urban angle distance between the branch and areas and local industries, such as power Shade-loving plants the main trunk of the tree) such as oaks plants. In addition, plants are affected by and hickories. A planting area that is large the area’s climate, wind and weather Scientific name Common name enough will be needed to support a patterns. Are large hills nearby? Areas Daphne x burkwoodii Carol Mackie daphne strong, extensive root system. directly east of hills or valleys between hills ‘Carol Mackie’ can lead to inversion layers and trapping Pest susceptibility of polluted air and smog levels that are Hamamelis spp. Witchhazels Whether or not a plant is pest-prone or dangerous not only to humans, but also to pest-resistant is important. Some species, Hydrangea arborescens Annabelle hydrangea plants. Air pollution can damage plant such as shrub roses, flowering crabapples, ‘Annabelle’ tissues and reduce photosynthesis. Some and hybrid elms, have disease-resistant species tolerate specific pollutants better Taxus spp. Yews varieties or cultivars that should be used than others. instead of the disease-prone types. Much Tsuga canadensis Eastern hemlock of the damage caused by insects and A few plants sensitive to air pollution diseases is only cosmetic or non-life include sugar and red maples, threatening. However, repeated defoliation mountainash, pagoda dogwood, American Wind or damage over the course of several years linden or basswood, eastern white pine, Constant winds increase a plant’s need for weakens a plant, making it more and Norway spruce.These plants typically water because of greater transpiration and susceptible to severe attack by another perform better in rural or suburban evaporation. Buildings in urban areas can pest or pathogen and may lead to the communities with good air circulation, but create a wind-tunnel effect and increase plant’s death. they perform poorly in downtown, highly the wind speed in those locations. Sites urbanized areas. Both native and exotic species are exposed to strong western or susceptible to insects and diseases. Choose southwestern winds should not only have plants that are either resistant or not adequate soil volume and moisture, but susceptible to various insects and/or also contain plants suited to this pathogens. Avoid planting evergreens environment that are not prone to winter such as Colorado blue spruce, Austrian and burn injury. Excessive winter sun and wind f i r e b l i g h t Scots pines, and Rocky Mountain juniper, on crabapple can burn broad-leaved and narrow-leaved as they are all highly susceptible to insects evergreens—in particular rhododendrons, and diseases. yews, and eastern hemlock.
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What type of landscape maintenance am I willing to provide? ? Salt tolerance Maintenance Black walnut toxicity Tolerance to road deicing salt, especially to considerations Black walnut and butternut trees and, to a sodium chloride (NaCl), is very important Trees and shrubs require proper much lesser extent hickories, produce a for plants near streets or sidewalks that are maintenance and pruning, especially in the toxin called juglone in all parts of the tree, heavily salted in winter. Salt damage may first 5–10 years.This will allow proper but especially in the buds, nut hulls, and be incurred from aerial salt spray, which is height, spacing, and clearance of larger roots.This toxin prevents many other common near roads with fast moving branches that grow over sidewalks or plants from growing under or near these traffic.This salt is deposited on foliage and streets.You will need to water often trees. Plants susceptible to juglone will be can cause significant damage to buds and (especially during hot, dry weather) until stunted and can wilt and/or die.These leaves. the plant is established which may take up include tomatoes, potatoes, eggplant, to 3 years. In general, slower growing trees Salt may also accumulate in the soil as peppers, and ornamentals such as lilacs, and shrubs require less pruning and tend snow melts, especially near roads or rhododendrons and azaleas, flowering to live longer with fewer structural sidewalks. Excessive soil salt can have a crabapples, and peonies.The toxic effects problems. major effect on a plant’s water and of a mature black walnut tree can extend nutrient uptake. Some plants tolerant to Be sure to consider the longevity of plants far away from the tree trunk, with the deicing salts include Kentucky coffeetree, you may select. Some popular plants, such greatest toxicity occurring within the tree’s Japanese tree lilac, chokeberries, and as white-barked birches, purpleleaf drip line. sumacs. For more information on salt sandcherry, Newport plum, and Colorado If you must plant in the vicinity of a black injury and plants tolerant to deicing salts, blue spruce, are short-lived in the urban walnut, it is essential to choose plants that see the UW-Extension publication Deicing landscape.You may choose to plant a are resistant. Even after a black walnut tree Salt Injury in the Landscape and Salt- particular tree or shrub, but if it is pest- and is removed, juglone will not be eliminated Tolerant Landscape Plants (A3869). disease-prone, it may die in a few years because the toxin is in the tree’s roots. It from infestation or infection. Some will take many years for the roots to decay Urban tolerance municipalities may prohibit planting of and toxin levels to diminish. Do not use Urban tolerance refers to a plant’s certain plant species that are known to be wood chips or bark pieces from a walnut tolerance to the cultural considerations a litter nuisance, hazard to people, tree as mulch. For more information on discussed above. Plants that tolerate an encourage insects, or harbor diseases. black walnut toxicity and plants tolerant or urban environment have the ability to Check with your city or municipality for susceptible to juglone see Black Walnut withstand harsh conditions such as information. Proper site and plant selection Toxicity (XHT1017, www.uwex.edu/ces/ extremes in temperature (both air and can reduce costs due to maintenance, wihort/GardenFacts.html). soil), extremes in moisture levels (both wet removal, infrastructure damage, and and dry), soil compaction, poor drainage liability. and aeration, pH extremes, low fertility, deicing salts, air pollution, high winds from air tunnels created between buildings, and restricted areas to develop roots and Are there any regulations or local shoots due to overhead and/or ordinances preventing me from planting? underground utilities. All these factors can significantly stress plants and increase ? their susceptibility to insects and diseases. Urban tolerance varies from plant to plant, but it can be enhanced with proper cultural practices, soil amendment, and species selection. Choose plants that are known to tolerate urban conditions if you live in a highly urbanized area. Some native species are appropriate for these extremes, while others are not. Urban soils are anything but native.
black walnut
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What existing vegetation exists in the area? ? Are there any invasive plants?
Native or exotic habitat andInvasiveness invasiveness A selection factor that you may wish to Exotic species have brought with them the consider is the native origin of a potential issue of ecological invasiveness. How plant choice. Is a particular species native invasive in the wild is this species? Avoid to your area? Planting exclusively native exotic species that are very invasive such species in the landscape can be beautiful as autumn-olive, black locust, buckthorns in a home garden, but in harsh urban (common and tallhedge glossy), conditions, many native plants perish due honeysuckles (Amur, Bell’s, Morrow’s, to poor soils, drainage problems, deicing Tatarian, Freedom, and Honeyrose), t a l l h e d g e salts, drought, and heat. Many exotic multiflora rose, Oriental bittersweet, glossy buckthorn ( i n v a s i v e ) species can be used in most residential Russian-olive, Siberian elm, and white landscapes, and very few of them are truly mulberry.These plants can take over invasive. Some are considerably more forested areas, replacing native species tolerant to urban conditions compared to and causing ecological damage. Even native plants. some native species could be considered aggressive because they reseed readily and/or spread quickly, such as boxelder and gray dogwood, the latter if it is growing in prairies. Avoid planting potentially invasive species such as Amur maple, burningbush, English ivy, European cranberrybush viburnum, Japanese barberry, Norway maple, vinca, and wintercreeper euonymus near natural or wooded areas.These species can readily spread in the wild through reseeding n a t i v e and/or suckering growth. p a p e r b i r c h
invasive buckthorn in forest understory
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How do I know if I am purchasing high-quality nursery stock? ?
Selectinghen selecting nursery high-quality nursery stock plants, make sure you pay particular attention to the factors below. Avoid buying stock that looksW questionable, even though it may be cheap. By properly selecting quality nursery stock in the beginning, you will have a head start on establishing a healthy landscape. Buy landscape plants from a nursery or garden center with a good reputation and people you trust. Chances are that an experienced, reputable nursery or garden center will have grown and maintained the plants properly and the plants will reliably establish in your garden if they are planted and maintained correctly.
Foliage A healthy, well-balanced crown should be visible. Foliage should be free of insects and diseases and turgid (not wilting).The leaves should be a healthy green color unless you are working with a yellow, blue, b a l l e d a n d purple, or variegated-leaf cultivar. Avoid burlapped trees plants with scorched or brown leaf margins; this indicates water stress. Roots If buying a balled and burlapped tree, Trunk, bark, and Roots are the most important part of a make sure the trunk is centered in the root branches plant, but they are often overlooked. ball and firmly attached without a loose or For trees, a straight, single, central leader is Examine the root system, if possible, on a damaged root ball. All plants should have a preferred, unless the plant is normally sold container-grown plant before you root ball that is adequate for the size of the as a multi-stem or clump form tree.The purchase it. Plants should be well-rooted crown or caliper of the trunk as specified trunk should be free of insect holes, and firmly established in the container. by the American Standard for Nursery damage, cracks, and sunken or swollen Healthy, white, fibrous roots with evenly Stock. A reputable nursery will have this areas. It should have good taper and flare distributed lateral roots should be information.The root ball should be moist appropriately at the base.The branches apparent. Avoid buying trees or shrubs at time of purchase and not dry. Avoid should be evenly distributed in the crown with circling or matted roots. Circling roots plants with weedy root balls, as you will preferably with a wide angle of in a container will need to be cut or have to remove the weeds before planting attachment between the trunk and the stretched out before planting in the soil to to avoid introducing them into your yard. branch.The branches should show good prevent future girdling roots (roots that Balled and burlapped root balls should be vigor and growth. Avoid buying trees with encircle the trunk and kill the plant). covered with natural burlap, not synthetic. lots of suckers (shoots) at the base or If purchasing bare-root stock, make sure watersprouts in the crown (shoots that do the roots have been kept moist with not bear flowers or fruit and are growing packing material or burlap, are adequately straight up and not outward). Underneath, spaced around the plant, and have no the top layer of bark on the branches circling or kinked roots. should be green. Brittle branches that break off easily are a sign of a dead or dying tree or shrub.
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Scientific names of plants
Arborvitae ...... Thuja occidentalis Arborvitae ‘Sunkist’ ...... Thuja occidentalis ‘Sunkist’ Arborvitae ‘Yellow Ribbon’ ...... Thuja occidentalis‘Yellow Ribbon’ Dirr, M.A. 1997. Dirr’s Hardy Trees and Autumn-olive...... Elaeagnus umbellata ReferencesShrubs: An Illustrated Encyclopedia. Azaleas...... Rhododendron spp. Timber Press, Portland, OR. Baldcypress...... Taxodium distichum Barberry, Japanese ...... Berberis thunbergii Rose, N., D. Selinger, and J.Whitman. 2001. Barberry, Japanese, Crimson Pygmy. . . . Berberis thunbergii Growing Shrubs and Small Trees in Cold ‘Crimson Pygmy’ Climates, Contemporary Books, Basswood...... Tilia americana Lincolnwood, IL. Bayberry,Northern...... Morella (formerly Myrica) pensylvanica Beech, American ...... Fagus grandifolia Beech, Purple-leaf ...... Fagus sylvatica f. purpurea Birch,Paper...... Betula papyrifera For more Birch,River...... Betula nigra To learn more about gardening in Birches,White-barked ...... Betula papyrifera, Wisconsininformation based on the latest university B. populifolia, B. pendula Bittersweet, American ...... Celastrus scandens research, visit the web sites of the Bittersweet, Oriental ...... Celastrus orbiculatus UW–Madison Horticulture Team BlackGum...... Nyssa sylvatica (www.uwex.edu/ces/wihort/) and Boxelder...... Acer negundo UW–Extension Publications Boxwoods...... Buxus spp. (learningstore.uwex.edu). Buckeyes ...... Aesculus spp. Buckthorn, Common ...... Rhamnus catharticus The following publications are available Buckthorn,Tallhedge Glossy...... Rhamnus frangula ‘Columnaris’ from UW–Extension Publications: Burningbush...... Euonymus alatus Guide to Selecting Landscape Plants for ButterflyBush...... Buddleja davidii Wisconsin (A2865). Describes the mature Butternut...... Juglans cinerea Chokeberry,Black...... Aronia melanocarpa height, shape, and preferred growing Chokeberry, Red ...... Aronia arbutifolia conditions for hundreds of trees, shrubs, Chokecherry,Amur...... Prunus maackii and vines. Clematis, Sweet Autumn ...... Clematis terniflora Plants Not Favored by Deer (A3727). A Clethra, Summersweet ...... Clethra alnifolia lengthy list of plants deer tend to avoid. Coffeetree, Kentucky ...... Gymnocladus dioica Cotoneasters...... Cotoneaster spp. Selecting Woody Landscape Plants for Fall Crabapples, Flowering...... Malus spp. Color: An Illustrated Guide (A3837). Crabapple, Cinderella® ...... Malus ‘Cinzam’ Brighten your autumn by including Crabapple, Firebird® ...... Malus sargentii ‘Select A’ ® plants with stunning fall color in your Crabapple, Harvest Gold ...... Malus ‘Hargozam’ Crabapple, Hopa ...... Malus ‘Hopa’ landscape. Crabapple, Red Jewel® ...... Malus ‘Jewelcole’ Deicing Salt Injury in the Landscape and Crabapple,Tina ...... Malus sargentii ‘Tina’ Salt-Tolerant Landscape Plants (A3869). Creeper,Virginia ...... Parthenocissus quinquefolia Identify and prevent salt injury. Includes Currant,Alpine...... Ribes alpinum an extensive list of salt-tolerant plants. Daphne, Carol Mackie ...... Daphne x burkwoodii ‘Carol Mackie’ Dogwood, Corneliancherry ...... Cornus mas Dogwood, Flowering ...... Cornus florida Dogwood, Gray ...... Cornus racemosa Dogwood, Pagoda ...... Cornus alternifolia Dogwood, Redtwig and Yellowtwig. . . . Cornus stolonifera Dogwood,Variegated Tatarian...... Cornus alba ‘Argenteo-marginata’ Douglas-fir...... Pseudotsuga menziesii var.glauca Elderberry, Black Lace™ ...... Sambucus nigra ‘Eva’ Elm,Siberian...... Ulmus pumila Euonymus,Winged...... Euonymus alatus Euonymus,Wintercreeper ...... Euonymus fortunei Falsecypress,Threadleaf, Golden Mop . Chamaecyparis pisifera ‘Golden Mop’
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Fir, Concolor or White ...... Abies concolor Forsythia, Border ...... Forsythia x intermedia Forsythia, Sunrise ...... Forsythia ‘Sunrise’ Fothergillas...... Fothergilla spp. Ginkgo ...... Ginkgo biloba Hackberry,Common ...... Celtis occidentalis Hawthorn,Winter King ...... Crataegus viridis ‘Winter King’ Hazelnuts...... Corylus spp. Hemlock, Eastern or Canadian ...... Tsuga canadensis Hickory, Shagbark ...... Carya ovata Honeylocust,Thornless, Skyline® ...... Gleditsia triacanthos var. inermis ‘Skycole’ Honeysuckle, Amur ...... Lonicera maackii Honeysuckle, Bell’s ...... Lonicera x bella Honeysuckle, Freedom ...... Lonicera ‘Freedom’ Honeysuckle, Honeyrose ...... Lonicera ‘Honeyrose’ Pine,Austrian...... Pinus nigra Honeysuckle, Morrow’s...... Lonicera morrowii Pine, Eastern White...... Pinus strobus Honeysuckle,Tatarian ...... Lonicera tatarica Pine,Ponderosa...... Pinus ponderosa Hornbeam, American ...... Carpinus caroliniana Pine,Red...... Pinus resinosa Horsechestnuts ...... Aesculus spp. Pine,Scots...... Pinus sylvestris Hydrangea, Annabelle...... Hydrangea arborescens Pine, Swiss Stone ...... Pinus cembra ‘Annabelle’ Phlox, Creeping ...... Phlox subulata Hydrangea, Climbing...... Hydrangea petiolaris Plum,Newport ...... Prunus ‘Newport’ Hydrangea, Panicle, Unique...... Hydrangea paniculata ‘Unique’ Poplars...... Populus spp. Ivy,Boston...... Parthenocissus tricuspidata Potentilla...... Potentilla fruticosa Ivy,English...... Hedera helix Quince,Flowering...... Chaenomeles speciosa Juniper, Creeping ...... Juniperus horizontalis Red-cedar, Eastern ...... Juniperus virginiana Juniper, Gold Coast® ...... Juniperus x pfitzeriana Redbud, Eastern...... Cercis canadensis ‘Aurea Improved’ Rhododendrons ...... Rhododendron spp. Juniper, Rocky Mountain ...... Juniperus scopulorum Rose,Multiflora ...... Rosa multiflora Juniper, Saybrook Gold...... Juniperus x pfitzeriana Rose,Rugosa...... Rosa rugosa ‘Saybrook Gold’ Rose,Shrub...... Rosa spp. Katsuratree...... Cercidiphyllum japonicum Russian-olive...... Elaeagnus angustifolia Lilac, Japanese Tree ...... Syringa reticulata Russian-sage...... Perovskia atriplicifolia Linden, American ...... Tilia americana Sandcherry, Purpleleaf ...... Prunus x cistena Locust,Black...... Robinia pseudoacacia Sassafras...... Sassafras albidum Magnolia, Butterflies ...... Magnolia ‘Butterflies’ Serviceberry, Apple ...... Amelanchier x grandiflora Magnolia, Leonard Messel ...... Magnolia x loebneri Snowberry...... Symphoricarpos albus ‘Leonard Messel’ Spirea, Japanese ...... Spiraea japonica Maple,Amur...... Acer tataricum subsp. ginnala Spruce, Colorado Blue ...... Picea pungens var. glauca Maple, Freeman, Autumn Blaze® ...... Acer x freemanii ‘Jeffersred’ Spruce,Norway...... Picea abies Maple, Miyabe, State Street® ...... Acer miyabei ‘Morton’ Spruce, Rainbow’s End Dwarf...... Picea glauca ‘Rainbow’s End’ Maple,Norway...... Acer platanoides Spruce, Sander’s Blue Dwarf ...... Picea glauca ‘Sander’s Blue’ Maple, Norway, Crimson King...... Acer platanoides ‘Crimson King’ Sumacs...... Rhus spp. Maple, Norway, Royal Red ...... Acer platanoides ‘Royal Red’ Tuliptree or Tulip-poplar...... Liriodendron tulipifera Maple,Red...... Acer rubrum Tupelo...... Nyssa sylvatica Maple,Silver...... Acer saccharinum Viburnum, American Cranberrybush, . . Viburnum trilobum Maple,Sugar...... Acer saccharum Compact ‘Compactum’ Maple,Three-flowered ...... Acer triflorum Viburnum, European Cranberrybush. . . Viburnum opulus Mountainash ...... Sorbus spp. Viburnum, Koreanspice...... Viburnum carlesii Mulberry,White...... Morus alba Vinca...... Vinca minor Musclewood ...... Carpinus caroliniana Walkingstick, Harry Lauder’s ...... Corylus avellana ‘Contorta’ Ninebark, Eastern, Diabolo® ...... Physocarpus opulifolius ‘Monlo’ Walnut,Black ...... Juglans nigra Ninebark, Eastern, Summer Wine® ..... Physocarpus opulifolius ‘Seward’ White-cedar, Eastern or Northern ...... Thuja occidentalis Oak,Black...... Quercus velutina Willow,CoralBark...... Salix alba ‘Britzensis’ Oak,Bur ...... Quercus macrocarpa Willow,Curly...... Salix matsudana ‘Tortuosa’ Oak,Chinkapin...... Quercus muehlenbergii Willow, Japanese Dappled...... Salix integra ‘Hakuro Nishiki’ Oak,Pin...... Quercus palustris Winterberry...... Ilex verticillata Oak, Swamp White ...... Quercus bicolor Wisteria, Kentucky ...... Wisteria macrostachys Pachysandra, Japanese ...... Pachysandra terminalis Witchhazel, Common ...... Hamamelis virginiana Pawpaw...... Asimina triloba Woodruff, Sweet ...... Galium odoratum Peonies...... Paeonia spp. Yews...... Taxus spp. Yuccas...... Yucca spp.
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Copyright © 2008 by the Board of Regents of the University of Wisconsin System. All rights reserved. Send inquiries about copyright permission to Extension Publishing, Rm. 231, 432 N. Lake Street, Madison,Wisconsin 53706. Author: Laura Jull is associate professor of horticulture, College of Agricultural and Life Sciences, University of Wisconsin–Madison and University of Wisconsin–Extension, Cooperative Extension. Produced by Cooperative Extension Publishing: Meg Gores and Linda Deith, editors; Susan Anderson, designer. Photo credits: Linda Deith—cover; iStockphoto.com—inside front cover, hydrangeas (p. 16), balled and burlapped trees (p. 19); Susan Mahr—garden path (p.21); Laura Jull and Ed Hasselkus— all other images. Reviewers: Jeff Iles, woody plant Extension specialist, Department of Horticulture, Iowa State University, Ames, Iowa, and Teryl Roper, former fruit crop Extension specialist, Department of Horticulture, University of Wisconsin– Madison, Madison,Wisconsin. Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, University of Wisconsin–Extension, Cooperative Extension. To see more publications or to order copies of this publication, visit our web site at learningstore.uwex.edu or call toll-free: 877-WIS-PUBS (947-7827). Choosing the Right Landscape Plants: Factors to Consider (A3864)
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