HOME & GARDEN

INFORMATION http://www.clemson.edu/extension/hgic HGIC 1709 1-888-656-9988 CENTER

Aquatic & Shoreline Selection

Aquatic plant selection is extremely important in invasive when planted under ideal conditions. These the development of aquatic pools. You must have should be planted in pots, if they are used at some degree of balance between plants and animals all. Other plants are considered to be nuisance in your pool so that the water remains clear and aquatic species. major problems with maintenance and filters do not arise. Plants are very important in pools. They The following plants are listed with state and produce oxygen through photosynthesis, which federal agencies as illegal plants: allows maximum fish health. Plants also take up • African oxygenweed (Lagarosiphon major) excess nutrients, particularly nitrogen and • Alligatorweed (Alternanthera philoxeroides) wastes from the fish. In certain • Ambulia (Limnophila sessiliflora) situations, ornamental pools can be stocked with • Arrowhead ( sagittifolia) only plants, with excellent results. • Arrow-leaved monochoria (Monochoria hastata) While numerous aquatic plants are available for • Brazilian elodea (Egeria densa) water gardens, it is important to consider certain • Common reed (Phragmites communis) factors when selecting plants for a water garden. • Duck lettuce (Otellia alismoides) These factors include water depth, sunlight and how • Eurasian watermilfoil (Myriophyllum each species relates to its surroundings. You can spicatum) obtain most plants from local garden centers or • Exotic burreed (Sparganium erectum) catalogs, but in many instances you can harvest • Giant salvinia (Salvinia auriculata, S. wild plants for use in garden ponds with proper biloba, S. herzogii, S. molesta) permission. • Hydrilla (Hydrilla verticillata)

• Mediterranean clone of caulerpa (Caulerpa Four general types of plants are available for taxifolia) aquatic use: • Melaleuca (Melaleuca quinquenervia) • Submerged plants, also called oxygenating • Miramar weed (Hygrophila polysperma) plants. • Mosquito fern (Azolla pinnata) • Shallow water or bog plants, which grow • along the water’s edge in natural Pickerel weed (Monochoria vaginalis) environments. • Rooted water hyacinth (Eichhornia azurea) • Floating plants, which are rooted in the • Slender naiad (Najas minor) bottom substrate and have floating • Water chestnut (Trapa natans) and . • Water lettuce (Pistia stratiotes) • True floating plants, which float on the • Water hyacinth (Eichhornia crassipes) surface of the water and whose roots are • Water primrose (Ludwigia uruguayensis) suspended in the water. • Water ( aquatica) • nightshade (Solanum tampicense) Two warnings should be heeded when selecting aquatic plants. Certain plants can become very The oxygenating plants are submerged plants, Floating Plants (deep-rooted aquatic plants with which many individuals often overlook. You can surface-floating leaves): plant them directly into the bottom, in pots, or • Hardy water lilies (Nymphaea species and simply weigh them down on the bottom. These cultivars) plants offer excellent fish habitat and are major • Tropical water lilies (Nymphaea species and sources of oxygen in pools. cultivars, such as N. capensis, N. colorata, N. gigantea, N. lotus, and N. Shallow water and bog plants work best in rubra) containers. These plants are rooted in the bottom, • Asian lotus (Nelumbo nucifera)** and grow above the water surface and generally have American lotus (Nelumbo lutea)** very showy flowers. They include cannas, irises, pickerel rush and other flowering aquatic plants. Shoreline, Shallow Water or Bog Plants: • Sweet flag (Acorus calamus) Most water gardens utilize floating plants, which • Japanese rush, Grassy-leaved sweet flag are rooted in the bottom. Examples of these plants (Acorus gramineus) are tropical water lilies, hardy water lilies, • Water plantain (Alisma plantago-aquatica) watershields and lotus. Tropical lilies are usually • Variegated striped rush (Baumea rubiginosa the best flowering plants. Some are day-blooming ‘Variegata’) while others are night-blooming. When designing • Native water canna (Canna flaccida) your pool, take into account when you will be • Gray canna (Canna glauca) viewing the pool. Tropical lilies cannot withstand • cold temperatures and will either have to be grown Black taro (Colocasia esculenta as annuals or brought indoors during winter in ‘Illustris’) South Carolina. Hardy water lilies are native to the • Southern swamp lily (Crinum americanum) area, and a number of varieties are available. The • Umbrella palm (Cyperus alternifolius) blooms are not as dramatic as the tropical water • Zimbabwe umbrella plant (Cyperus lilies, but they survive outdoors during the winter. involucratus) The lotus can be a beautiful plant, but since it is • Egyptian paper reed (Cyperus papyrus) known to spread rapidly and become invasive in • Water bamboo (Dulichium arundinaceum) natural ponds and lakes, it should be planted in pots. • Star sedge (Dichromena colorata) Watershield is also invasive and should be planted • Creeping burhead ( cordifolius) in pots. • Horsetail (Equisetum hyemale) • Variegated water grass (Glyceria maxima True floating plants are generally not recommended var. variegata) in pools in South Carolina. They are the most • Hardy white butterfly (Hedychium invasive weed group. coronarium) • Scarlet swamp hibiscus (Hibiscus coccineus) The following Aquatic plants are recommended for • Swamp rose mallow (Hibiscus moscheutos) South Carolina*: • Variegated spider lily (Hymenocallis caribaea ‘Variegata’) Submerged Aquatic Plants ("oxygenators" or • Spider lily (Hymenocallis caroliniana) oxygen-producing plants): • Blue iris (Iris versicolor) • Gray fanwort (Cabomba caroliniana)** • Japanese iris (I. ensata) • Coontail (Ceratophyllum demersum)** • Siberian iris (I. siberica) • Tape grass or Eel grass (Vallisneria • Yellow water iris (I. pseudoacorus) americana) • Corkscrew rush (Juncus effusus ‘Spiralis’) • Parrot’s feather (Myriophyllum • aquaticum)** Water mint (Mentha aquatica) • • Underwater banana plant (Nymphoides Bog bean (Menyanthes trifoliata) aquatica) • Lavender musk (Mimulus ringens) • Little floating heart (N. cordata) • Water forget-me-not (Myosotis scorpioides) • Flamingo plant (Oenanthe javanica regulate the importation of non-native aquatic ‘Flamingo’) species into the state and should be contacted if any • Golden club (Orontium aquaticum) plants not mentioned in this list are to be brought • Water arum (Peltandra virginica) into the state. Contact Chris Page at • Pickerel rush (Pontederia cordata) [email protected]. • Giant pickerel rush (Pontederia cordata var. lancifolia) **May be invasive. • Lesser spearwort (Ranunculus flammula) Prepared by Jack M. Whetstone, Extension Aquatic Specialist; D. • Common arrowhead or Duck Lamar Robinette, Extension Aquatic Specialist; and Bob Polomski, (Sagittaria latifolia) Extension Consumer Horticulturist, Clemson University. (Revised • Double arrowhead (Sagittaria sagittifolia 02/00.)

‘Flore Pleno’) This information is supplied with the understanding that no • Lizard’s tail (Saururus cernuus) discrimination is intended and no endorsement by the Clemson • Club rush (Schoenoplectus lacustris subsp. University Cooperative Extension Service is implied. All recommendations are for South Carolina conditions and may not tabernaemontani) apply to other areas. Use pesticides only according to the directions • Thalia (Thalia dealbata) on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status • Red-stemmed thalia (Thalia geniculata f. of registration and use patterns are subject to change by action of ruminoides) state and federal regulatory agencies. Follow all directions, • Graceful cattail (Typha laxmannii) precautions and restrictions that are listed.

*The South Carolina Department of Natural Resources Aquatic Nuisance Species Program helps

The Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, sex, religion, national origin, disability, political beliefs, sexual orientation, marital or family status and is an equal opportunity employer. Clemson University Cooperating with U.S. Department of Agriculture, South Carolina Counties, Extension Service, Clemson, South Carolina. Issued in Furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of May 8 and June 30, 1914 Public Service Activities