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Home , Fertilizer burn, Micronutrient deficiency

Home & Garden Pest Management Guide For British Columbia

2019 Edition

Chapter 7 Management and Composting

Soil Management and Composting

Availability of nutrients to depends on “Feed the soil not the .” The how healthy the soil is - good soil tilth will goal of managing a garden soil lead to better nutrient supply. To maintain should be to ensure that the soil is good and tilth, organic matter healthy. and nutrients should be added regularly. The pH of the soil, which measures how acid it is, will affect nutrient Healthy, vigorous roots make healthy, uptake as will the salt content of the soil.(see vigorous plants. Many plant health problems “Lime and Soil pH”, below). are the result of poor root growth. A suitable soil for growing healthy roots and plants must be fertile and have a good structure or Organic Matter “tilth” which permits air and water movement around the roots and good root Organic matter is primarily added to soil to penetration and growth. improve its physical structure. Depending on the source and degree of decomposition of Soil texture, or the relative amounts of sand, the organic matter it may also supply silt and clay in the soil, imparts most of the nutrients. Organic matter breaks down in the physical characteristics of the soil. Soil soil to form humus. Organic matter can structure, or the arrangement of the lumps improve air and water movement in a clayey within the soil, provide a visual key to soil soil and makes it easier to work. Organic tilth. A “light” soil with a high percentage of matter also improves the water and nutrient- sand or gravel may allow water and nutrients holding capacity of sandy . Organic to drain or “leach” out too quickly for most matter should be applied regularly to plants. A sandy soil will also tend to have vegetable gardens, woody ornamentals, and smaller lumps or be single grained. A flower beds. “heavy” soil with a high percentage of clay will tend to become waterlogged and will Organic matter suitable for gardens comes not allow enough air to get to the roots. Clay from a ranges of sources including yard and soils tend to have harder lumpy tilth. A soil garden waste (leaves or grass clippings), that is compacted or hardened will not allow animal manures, , peat moss, roots to penetrate and grow well. A “loamy” seaweed, and wood products (sawdust, soil is generally a soil with a mixture of shavings or bark mulch). Peat moss is useful sand, silt and clay particles which, combined as a , but supplies almost no with organic matter, create a friable or well nutrients. The ability of organic matter to aggregated and crumbly structure. supply nutrients depends on its source, particles size and degree of decomposition. A fertile soil is one which contains all of the If wood products such as sawdust are used, essential nutrients (minerals) needed by the extra may have to be applied if dry plants for growth. These nutrients must be fertilizer is used. For every layer of sawdust available in sufficient quantities and in a 5 cm deep, add an extra 65 grams of 46-0-0 form that can be taken up by plant roots. urea fertilizer, 190 grams of 16-20-0

Soil Management and Composting - Home and Garden Pest Management Guide 7-1 (ammonium-phosphate-sulfate) per 9 square rather than composting it. Homeowners meters (100 square feet), or equivalent usually add ingredients in small quantities; amount of nitrogen in addition to whatever therefore the doesn't usually get amount of nitrogen is needed by the crop. very hot. This is referred to as "cold Applications of liquid fertilizer should not composting". It doesn't kill everything, but be affected by the sawdust and do not need produces good compost. Properly composted to be increased. material should look dark and spongy, and have a fibrous, moist texture. Manures and composts are among the best materials to add because they add organic Compost Preparation matter to soil, often improving aeration, drainage, nutrient-holding capacity, and Compost is produced by the decay of biological activity and other soil properties. vegetative (plant) matter. Compost is a soil However, nutrient levels vary among conditioner, a source of organic matter different composts and most composts do available to all gardeners. Choosing a not supply nutrients in the same ratios that compost site carefully is very important. are needed by plants. If composts are made Partial shade is ideal, to avoid summer from a significant amount of manure, drying and also provide some solar heat to nutrient levels tend to be higher compared to onset composting action. To prevent too other composts such as yard trimmings much moisture loss, choose a site that is compost. Heavy applications of compost protected from drying winds. Locate your may supply high levels of soluble salts, composting site in a spot that is which can be damaging to plant roots. If wheelbarrow accessible to make it easier to composts derived from animal manures are move compost volumes in and out. going to be used in raised beds, containers or planters, the volume of compost should be Compost is made by alternating layers of less than one third of the total volume of “green and brown” material. Examples of ‘soil’ in the container. Weed seeds can be green materials include kitchen waste, grass introduced into the garden by adding clippings, and fruit and vegetables. immature compost or material that has not Examples of brown material include leaves, fully composted, regardless of whether it newsprint, and shredded paper. Do not add contains manure. meat, bones, or dairy products which can attract animals and vermin. Adding a light Composting dusting of soil every few layers will assist the earthworms in breaking down organic Composting is very beneficial to the garden material. Store vegetative matter until and the environment. If plant material is enough is accumulated to make a pile. Chop properly composted at the right temperature, up large, coarse pieces before added them to most insects, diseases and weed seeds may the pile. Materials used in building compost be destroyed. Home composting may not piles should be moist, but not waterlogged. destroy all of these if proper temperature and For example, a large pile of wet grass moisture is not maintained. If weed seeds or clippings will not compost as well as a pile certain pests or diseases are present, it is made of layers of different materials varying advisable to dispose of crop refuse in a in moisture content and texture. Turn or landfill where it will be quickly buried, aerate the compost pile frequently (every

Soil Management and Composting - Home and Garden Pest Management Guide 7-2 few weeks or more often) to introduce garden with ripened seeds; and lawn oxygen into the pile. Some plastic compost clippings that have been recently treated bins are not suited to "turning". Compost with weed killer. Avoid highly resinous aerating tools (Wingdiggers) or a sharp wood and leaf prunings from conifer plants stake, can help accomplish this task. A such as junipers, pine, spruce and arborvitae. properly constructed compost pile will not The resins protect these materials from emit offensive odours, but will produce a lot decomposition and extend the time needed of heat. for composting in comparison with other plant materials. This type of plant material If compost is made inside a covered bin or should be buried, taken to a landfill, burned box, heat will be retained. A cover is (where permitted), or placed in plastic recommended in the coastal area to garbage bags and set out with the household encourage heating, prevent loss of moisture garbage for disposal (where permitted). in the summer and reduce leaching by the winter rains. This results in faster Compost piles built in the spring should be decomposition and kills most insect pests. In ready for use in the fall. Those constructed the dry areas of the Interior, a cover is not so in the fall may be ready by spring or early essential and it is more important to add summer of the following year. In regions water periodically during dry weather. The with heavy winter rains, if the compost box box should have holes or gaps in the sides has no permanent cover, use a plastic sheet and bottom to allow air to enter. during the winter to permit faster decomposition and reduce leaching of The ideal is to have three receptacles: one nutrients. Excess water will cause piles to for storage of incoming vegetative materials, become “anaerobic” from lack of oxygen one for the working pile, and one for the and decomposition will stop. finished product. Most homeowners only have space for one compost bin. This is why Composting Pest Problems the plastic covered bins have a door at the bottom, so finished compost can be moved Rats may look at a compost bin as an ideal out, while new material is added to the top. site to nest in. Try to keep compost moist It is also possible to remove the front of a and regularly turned to make a compost pile wooden box and slide the box to a new unattractive. Rats may be looking for food in location before re-attaching the front so that the pile so be sure to bury food scraps. it can be refilled. This eliminates the cost of Consider building an enclosed bin for building three boxes. Screening is not kitchen waste and have an open bin for grass necessary unless a finer product is required clippings and garden waste. Never add for lawns or containers. Non-decomposed, meats, greasy foods or dairy products to a coarse materials can go back to the working compost bin. Always make sure bin lid is pile for further decomposition. secured. If rats are burrowing underneath the compost, stand the bin on ¼ inch mesh wire. Some plant material should not be If rats are gnawing into a plastic bin, try composted. This includes plant parts reinforcing the sides, top and bottom with ¼ containing certain insects and diseases, such inch mesh wire. as root maggots or clubroot of crucifers; mature weeds and plants from the flower

Soil Management and Composting - Home and Garden Pest Management Guide 7-3 Fruit flies can become a problem if food is Compost Tea: A Growing Concern left exposed, or if there is too much food in the bin. Always bury food, do not overload The term “Compost Tea” describes the the bin, and consider covering the surface of watery solution obtained by soaking the bin with a plastic sheet, old carpet or compost in water in the presence of nutrients sacking. Freezing food prior to composting such as molasses, kelp, and rock dust. The may also help. If this problem persists, move term “Compost Tea” is sometimes used to the bin to a location where the flies will not include the following products: be so bothersome.  Compost leachate - leachate from the Unpleasant odour can result from improper compost pile nitrogen/carbon layering, not enough air, too  Compost extract - soaking compost much moisture or too many acidic foods in water such as citrus peels. Ensure proper aeration  Manure tea - soaking manure in by checking if holes are clear, or drill more water holes. If there is not enough air in the  Herbal tea - soaking fresh green plant compost, aerate. Cut back on acidic food, material in water and consider adding dolomitic lime. Adding  Liquid manure - fermented plant and course, dry materials such as straw can help. marine animal material

If raccoons become a problem, do not put Compost teas are sometimes used as liquid food of any kind in open compost piles; or to suppress plant diseases. instead, use a securely covered compost structure or a commercially available Compost Teas and Food Safety raccoon-proof composter to prevent attracting raccoons. A covered worm box is Compost teas that are improperly prepared another alternative. If burying food scraps, may contain pathogens, such as Salmonella cover them with at least 8 inches of soil and and E. coli 0157:H7. Gardeners using don’t leave any garbage above ground in the compost tea must be certain that the area—including the stinky shovel. Placing a compost tea does not contaminate food wire mesh barrier that is held in place with a plants with organisms that can cause human heavy object over the in-ground compost illness. Since the microbial composition of a will prevent problems. home made compost tea can not be controlled, it is risky to use compost teas, and they are not necessarily effective for managing plant diseases.

If using compost teas, apply only to the soil as a weak fertilizer. Do not apply to plant foliage or fruit that will be eaten.

Soil Management and Composting - Home and Garden Pest Management Guide 7-4 Lime and Soil pH The two best liming materials for use in the home garden are ground limestone (

carbonate - CaCO ) and dolomite lime Many soils, particularly those on the Coast, 3 (calcium/ carbonate - CaCO • are subject to leaching from heavy rainfall, 3 MgCO ). Properly applied, either of these resulting in an acidic (low pH) or “sour” soil 3 materials will gradually increase soil pH, that can limit plant growth. A few plants, making the soil more alkaline, and will hold such as camellias, rhododendrons, azaleas, this pH level for a few years. Lime is slow to Fraser firs, mountain laurels and blueberries react with soil so it should be mixed into the prefer acidic soils. For others, applications soil or applied in fall so that winter moisture of lime may be needed to neutralize soil can move it into the soil. Avoid adding acidity (raise the pH) and, to a lesser degree, sources of nitrogen (e.g., some composts, to supply calcium. If dolomite lime is used, ammonium-based fertilizer) at the same time magnesium, which is often deficient in as liming, since the lime and nitrogen will coastal soils, will also be supplied. react together to result in nitrogen losses into

the air. Many regions of the province, particularly those in the Interior, have naturally Calcium hydroxide, Ca(OH) , also known as occurring high pH (alkaline) soils. These 2 hydrated lime, is not recommended for home soils should not be limed, unless the pH has gardens. It can burn roots or other plant parts been decreased (artificially) below optimal on contact, therefore it should be used only levels for the crop. The pH of alkaline soils on ground being prepared for seeding and/or can be lowered through the use of small planting. Excess calcium hydroxide may amounts of finely ground fertilizers. make the soil too alkaline and reduce the Over time, the addition of certain nitrogen availability of some nutrients. It also breaks fertilizers will also acidify soil. Many down organic matter in the soil. It should alkaline soils tend to have higher salt never be used on lawns as it encourages contents. Additions of organic matter will certain diseases of turf. also aid in buffering high pH and higher salt contents. Salts may need to be leached from Raising the soil pH is best done by the soil. If calcium is required in high pH thoroughly incorporating lime into the top soils, apply gypsum (calcium sulphate) 15-30 cm of soil the year before planting. which provides calcium without raising the Thereafter, top-dressing established pH. plantings with lime will help to maintain the

pH at more neutral levels. Ideally, lime The need for lime and how much to apply is should be worked into soil well before best determined by a soil test. A relative pH planting. If necessary, lime may be applied level can be obtained by using a quick test or at planting time along with fertilizer, but pH probe (purchased from a garden centre) work the lime in thoroughly and follow which may be sufficient for the home planting with a thorough watering or garden. Soil testing laboratories can provide irrigation. For most coastal soils, an a more accurate measure of pH, along with a application of lime every 3 to 4 years will complementary measure (e.g., buffer pH) maintain the soil pH at a level suitable for that is needed to provide a lime most plant growth. recommendation.

Soil Management and Composting - Home and Garden Pest Management Guide 7-5 In coastal vegetable gardens, finely ground sufficient amounts of , but limestone or dolomite should be applied sometimes they may be deficient or even in every 2 or 3 years at the rate of 20 kg/100 m2 excess, which can damage plants. and incorporated while digging or rotovating. This is best done in the fall or Manures and Composts early spring, at least a month before planting. Do not apply lime where potatoes Manure is both an organic matter source as are to be grown, as high soil pH promotes well as a nutrient source. Animal manures scab disease. and composts may provide enough major plant nutrients for a garden. Because of its In coastal flower and shrub beds, apply 20 high nutrient content, compost derived from 2 kg/100 m of ground limestone or dolomite manure, fish meal or biosolids should be lime and incorporate before planting. After used as a fertilizer. High rates of manure use initial establishment, lime may need to be should be avoided as this can lead to applied to perennial beds as a top-dressing leaching or runoff loss of nutrients. 2 every few years at 5-10 kg/100 m . If large quantities of manure are available, 2 For lawns, 25 kg/100 m of ground other fertilizers may not be required. limestone or dolomite can be incorporated However, animal manures can vary in their into the topsoil before seeding or sodding. ability to supply nutrients depending on their Fall liming is recommended to allow winter origin, age, and the method of storage. When rains to move the lime into the soil. storing manure, cover it with plastic to 2 Thereafter, 12-25 kg/100 m may be applied prevent leaching. If sufficient quantities of to the lawn surface every 2 to 3 years as a manure are not available, use whatever top-dressing to maintain pH and reduce the organic material is available and supplement growth of moss. Note: Liming lawns this with commercial fertilizers if necessary. encourages the growth of some broad-leaved plants such as white clover. Application rates for fresh manure should be equivalent to approximately 2 centimeters in Fertilizers depth or 50 kg per 10 m2. A notable exception is poultry manure that has not Soils must supply multiple elements been composted. This material has a much for plants to grow properly. If any one higher nitrogen content than cattle or horse manure and should be applied at closer to 5 essential element is deficient, plant growth 2 will suffer. Elements required by plants in kg per 10 m , or it should be composted with the largest amounts are nitrogen (N), other materials before being applied. (P), and (K). Nitrogen is usually the most limiting, especially in Caution: Fresh animal manure may contain high rainfall areas such as coastal B.C. potentially harmful organisms. To avoid risk Nitrogen, P and K are called “major” or of infection from pathogens, manure should “macronutrients” and are represented by the be composted for at least one year prior to three numbers on a fertilizer label (e.g., 46- use or it should be incorporated into the soil 0-0 indicates a fertilizer is 46% nitrogen by for use with long season crops such as corn weight). The other minerals are needed in or late potatoes. Do not use fresh manure on smaller amounts and are called “minor” or short season crops such as radishes or leaf “micronutrients”. Most soils contain .

Soil Management and Composting - Home and Garden Pest Management Guide 7-6

Approximate Composition of Fresh Manure* (%)

Manure Moisture Nitrogen Phosphate Potash Chicken 55 2.7 2.5 1.1 Cattle 80 0.5 0.3 0.8 Hog 75 0.5 0.2 0.4 Horse 60 0.3 0.2 0.3 Spent Mushroom 65 0.6 0.2 0.8 Compost Sheep 65 0.9 0.8 0.9 * Nutrient content of manure will vary widely depending on the type and amount of bedding used, the age of the manure and the storage method.

Composition of Dried & Bagged Manure

Many types of bagged manure are sold in roots. Read the label carefully and apply as garden centres. These products have only directed. 10-20% moisture and are 2 to 8 times more concentrated in terms of nutrient content Examples of organically-derived fertilizers than fresh manure. Like compost, manure include fish fertilizers and blood meal should make up less than 15% of the total (nitrogen suppliers), bone meal (phosphorus volume of soils used in containers or raised supplier), greensand, wood ashes, and beds due to the higher nutrient concentration seaweed (potassium suppliers). and potential for manure to contain salts. Slow-Release Fertilizers:

Commercial Fertilizers Several types of coated, slow-release fertilizer pellets are used in ornamental Commercial fertilizers may be derived from nurseries. The slow release is created by organic or inorganic materials. coating or mixing the fertilizer pellets with sulfur or some form of polymer resin. They Organic Fertilizers: can be recognized as small white, yellow or grey round pellets on or in container plants Organically-derived chemical fertilizers purchased at garden centres. Although they become available to plants slowly. These are “slow-release” products, over- types of fertilizers must undergo various application next to stems can cause burn of reactions in the soil in order to supply plants at the soil line. In the home landscape, nutrients in the form absorbed by plants. another type of season-long, slow-release Because organic fertilizers become available fertilizer for woody ornamentals is in the slowly, fertilizer or salt burn of plants is less form of a small stake which is driven into likely than when using highly concentrated the ground near a shrub or woody perennial. mineral fertilizers, but can still occur if too much is applied to young, tender plants and

Soil Management and Composting - Home and Garden Pest Management Guide 7-7 Chemical Fertilizers: What Fertilizer to Use and How Much? Chemically-synthesized fertilizers are relatively inexpensive and readily available. Fertilizer requirements for crop phosphorus They are prepared in a form that is readily and potassium requirements are best absorbed by plant roots. Most fertilizers for determined by a soil test before planting. home gardens are mixtures of urea (46-0-0); Nitrogen requirements depend mainly on the di-ammonium phosphate (NH4)2HPO4, (18- crop type and less so on soil tests. Soil 46-0); and muriate of potash (KCl, 0-0-60). nutrient levels can be determined by using a Balanced fertilizers for use by home quick test kit (purchased from a garden gardeners are made by mixing these centre). Soil testing laboratories can provide fertilizers in varying proportions. a more accurate measure of soil nutrient levels and needs (refer to your local garden Composition of Fertilizers: centre for suggestions for a testing lab).

All packages of commercial fertilizers, Generally, fertilizers that are relatively high whether organic or chemically-synthesized, in nitrogen are used in the spring to promote have 3 numbers on the bag or box. These vegetative growth, for example, leafy numbers indicate the percentage by weight vegetables, lawns, young trees and shrubs. of nitrogen (N), phosphate (P2O5) and potash These should not be applied in late summer (K2O) in the blend. Note that P2O5 and K2O to perennial or woody plants which need to are simply units of phosphorus and “harden off” before winter. Fertilizers potassium, not the actual forms of nutrients relatively high in phosphorus and potassium that plants take up. are used to promote production of flowers, fruits, or roots. For Example:  4-10-10 = 4% nitrogen, 10% The following rates are recommended as phosphate, 10% potassium general guidelines. Other fertilizers of higher  6-8-6 = 6% nitrogen, 8% phosphate, analysis but similar ratios can be substituted 6% potassium at lower rates, for example, instead of using  46-0-0 = 46% nitrogen, 0% 15 kg of 4-10-10, you can use 7 kg of 8-24- phosphate, 0% potassium 24. Do not use excessive rates or crop damage in the form of may When deciding how much fertilizer to apply, result and nutrients will be lost to the the composition of the blend must be taken environment by runoff or leaching. If into account. manures or composts are also used, apply lower rates of fertilizer. Do not apply For Example: concentrated fertilizer to leaves or close to A 10 kg bag of 46-0-0 contains almost as the roots or stems of plants. Never put much nitrogen as a 75 kg bag of 6-8-6. There fertilizer in the seed furrow in close contact are 4.6 kg of nitrogen in one 10 kg bag of with the seeds or in the transplant hole in 46-0-0 (46% nitrogen x 10 kg = 4.6 kg). contact with the roots, as this may burn new A 75 kg bag of 6-8-6, (or 7.5 X 10 kg bags) seedlings. contains 4.5 kg of nitrogen (6% nitrogen x 75 kg = 4.5 kg).

Soil Management and Composting - Home and Garden Pest Management Guide 7-8 Fertilizing Vegetables afterwards to wash the fertilizer into the root zone. If soil is high in organic matter, or Broadcast one of the following fertilizer manure or compost was applied, side- formulations over the garden and dressing should not be necessary. incorporate into the top 15 to 20 cm of soil just before planting. Fertilizing Lawns

Fertilizer Fertilizer Rate Prior to seeding or sodding a new lawn, kg/100 m2 apply one of the following fertilizer Coastal Gardens: formulations and incorporate it into the top 4-10-10 12-15 several centimeters of the soil. 6-8-6 12-15 Interior Gardens: Fertilizer Fertilizer Rate kg/100 m2 16-20-0 4-5 Coastal Lawns:

For leafy vegetables, carrots and corn, apply 13-16-10 8 a side-dressing of one of the following 8-10-6 13 nitrogen fertilizer formulations after the Interior Lawns: plants are well established. 21-0-0 6 16-20-0 7.5 Fertilizer Fertilizer Rate kg/100 m2 Once established, the lawn will require Calcium Nitrate 4 periodic fertilizer applications to maintain 15.5-0-0 vigour. Apply one of the above fertilizers at 21-0-0 3 half rate, or a dressing of well rotted, 46-0-0 1 screened manure or compost, in the spring and again in the fall. Calcium nitrate (15.5-0-0) is one of the best products to use in coastal home gardens Broadcast fertilizer evenly over the lawn and because it also provides 20% calcium; does water afterwards to wash fertilizer into the not lower soil pH; is least likely to burn root zone and prevent burning of the grass. plants and can also be used to make up foliar Slow release fertilizers such as SCU spray applications to correct calcium (sulphur-coated urea) are useful in deficiencies. Do not apply calcium nitrate prolonging the nutrient release and reducing just before significant rainfall or before the danger of burning. excessive watering, to avoid leaching the nitrate-nitrogen below the root zone. Other Some lawns, particularly those growing on sources of nitrogen, such as ammonium soil low in organic matter , or sandy soils sulfate, lower soil pH and so would be more low in clay content, will require 2 or 3 appropriate for use in the Interior. additional applications of nitrogen during the season. Example: 46-0-0 at 1 kg/100 m2. Dribble the fertilizer alongside the plant Slow-release fertilizers are helpful on sandy row. Do not place fertilizer in direct contact soils. with plants, but keep it back about 10 cm from the roots. If the soil is dry, water

Soil Management and Composting - Home and Garden Pest Management Guide 7-9 Fertilizing Flower Beds, corrective program. The micronutrients most Ornamental Trees and Shrub commonly found to be deficient in B.C. are Borders boron, calcium, magnesium and .

One of the easiest ways to apply For annual or newly established perennial micronutrients is to use a chemically- flower beds, apply a complete fertilizer such synthesized, complete fertilizer which, in as 4-10-10 at 12-15 kg/100 m2 and addition to containing nitrogen, phosphorus incorporate into the top several centimetres and potassium, also contains micronutrients, of the soil before planting. for example: “20-20-20 plus minor

elements”. Follow package instructions to For trees and shrubs, apply a complete determine rates of application. If using fertilizer high in nitrogen, such as 28-14-14 fertilizers containing minor elements or 12-4-8 at label rates, four to six weeks (micronutrients), careful measuring is after planting. An annual spring application essential to prevent accidental overdoses. thereafter will be sufficient to maintain vigour. Fertilizer should be broadcast over Fritted-trace-elements (F-T-E), containing the area extending from the trunk to slightly boron, , magnesium and zinc carried on beyond the spread of the branches. As a rule glass beads, can be purchased for garden of thumb, use about 200 g of 10-5-5 for each plantings and houseplants. Only use F-T-E at cm of trunk diameter. the recommended rates on the label and mix

thoroughly into the soil. Micronutrients are Micronutrients also available in chelated or organic based forms. In addition to nitrogen, phosphorus and potassium, plants require small amounts of Boron (B) other micronutrients including calcium, magnesium, sulphur, iron, , Boron deficiency is found in fruit trees in boron, copper, zinc and . some parts of the Interior. Boron deficiency Where manures or other organic materials shows up in the youngest leaves and are applied regularly, deficiencies of these terminal buds. Leaf tips and margins of nutrients rarely occur. Commercially affected plants may have a scorched synthesized, complete fertilizers may be appearance. Young leaves of trees may purchased that will supply these become pale green, twisted and often die. If micronutrients as well as nitrogen, severe enough, terminal buds will die. phosphorus and potassium. Similar symptoms can be caused by diseases and other factors, so a laboratory diagnosis Where limited manure or compost has been may be needed to eliminate other causes. used or under certain soil and climatic conditions, a deficiency may Root vegetables such as beets, carrots, occur in a crop or landscape planting. These rutabagas and parsnips may be affected by deficiencies can be corrected by adding a boron deficiency at the Coast or in the fertilizer containing micronutrients to the Interior. Affected roots may crack, or soil or by spraying micronutrient solutions internal tissues may become discoloured and onto the plants. A reliable diagnosis or soil darken, resulting in a disorder known as test should be carried out before beginning a

Soil Management and Composting - Home and Garden Pest Management Guide 7-10 “blackheart”. A mild boron deficiency to apply to the soil, use 2 tablespoons per 4 symptom frequently seen in beets is a series L and apply to 3 m of row with a watering of whitish concentric rings in the roots when can. they are sliced open. “Blackheart” of potatoes is usually caused by other factors. Note: Do not apply boron to areas where cucumbers or beans are to be grown. Other boron deficiency symptoms in vegetables include brown curd of Calcium (Ca) cauliflower where the normally white cauliflower florets develop a tan or brownish Calcium deficiency is not always apparent in cast; hollow stem in cole crops where stems the growing plant but shows up at harvest or are hollow and cracked; and, cracked stem shortly thereafter. Bitter pit of apple, of celery characterized by ragged, crosswise blossom end rot of tomatoes and peppers cracking and stiff, brittle, bitter-tasting and black heart of celery are all due to stems. shortage of calcium in the fruit tissues. Calcium is taken up by the roots but is not In strawberries, boron deficiency causes readily translocated (moved) between parts stubby, distorted fruit and crinkled, distorted of the plant, so foliar sprays of calcium on leaves. However, these symptoms are also vegetable crops after fruit are formed are caused by mites, viruses and other factors, so usually ineffective. On apple trees, calcium a good diagnosis is important. foliar sprays are beneficial if applied early enough, before the fruit size up. There is In flowers, boron deficiency typically causes some evidence that calcium foliar sprays blackening of young shoots and flower buds. might be beneficial to reduce fruit drop in Calcium deficiency or virus infection can particular varieties of highbush blueberries cause similar symptoms. Boron deficiency is (e.g., Draper). Calcium nitrate at 1-2 rare in flower gardens and woody shrubs and teaspoons (5-10 grams) /L of water should perennials. be sprayed on the fruit as it is sizing up to increase calcium uptake. For tomato, pepper While boron is a required element, most and other vegetable crops, reduce nitrogen plants can be damaged by an excess of this fertilizer, check that soil pH is appropriate, nutrient. Therefore, when applying a boron avoid drought-stress at flowering and early fertilizer, careful measuring is essential. In fruit stage, and apply calcium-containing the Interior especially, boron carry-over may soil fertilizers in the spring. be a problem because there is less leaching of boron from soils over the winter. Calcium deficiency also causes distorted and Therefore, do not apply boron unless a soil twisted leaf tips on strawberry and test indicates a need. blackening of buds and young shoot growth on garden flowers, although this is more The most common method of applying common in commercial greenhouses than in boron is to mix borax, which contains 11% outdoor home gardens. It can be mistaken boron, in water and either spray this solution for boron deficiency, mites, aphids or other on foliage, or water it into the ground at factors. For strawberries grown on sandy planting time. For foliar sprays, mix one soils, follow recommendations above for level tablespoon of borax with 4 L of water; tomatoes and peppers.

Soil Management and Composting - Home and Garden Pest Management Guide 7-11 Iron (Fe) Organic Fertilizers De- Mystified Iron deficiencies can occur on broad-leaved evergreens, bush fruit and strawberries Fertilizer application can be a challenge in growing on high pH soils, especially in the terms of understanding the correct amount to Interior. It can also occur on rhododendrons apply to your garden plants. This can be at the Coast. Iron appears first on even more challenging when organic the youngest leaves as interveinal yellowing, sourced materials are used. The following progressing to an overall pale green or table provides some detail on many types of yellow leaf colour. Iron fertilizers specially organic soil amendments including the formulated as an iron chelate (Fe + EDTA) nutrients they contain and a recommended should be used at rates indicated on the application rate. The application rates are label. Iron deficient plants may also be conservative but are designed to provide sprayed with ferrous sulphate at 1 teaspoon sufficient plant nutrients under average soil (5 grams) in 2 L of water. and climatic conditions.

Magnesium (Mg)

Magnesium deficiency is frequently observed in conifers growing at the Coast. The typical symptom is a general yellowing of the needles, starting with the oldest needles. Addition of dolomite lime to the soil at planting should prevent Mg deficiency (see “Liming and Soil pH”, above). Epsom salts (MgSO4) at 2 teaspoons (10 grams)/L of water, sprayed on the plants or other fertilizers containing magnesium, can be used to alleviate this problem temporarily.

Zinc (Zn)

Zinc deficiency on fruit trees is characterized by an interveinal yellowing of younger leaves followed by a reduction in leaf and shoot growth. If severe enough, leaves may grow in a “rosette” form. is most commonly observed in the Interior, since zinc availability decreases with increasing soil pH.

Soil Management and Composting - Home and Garden Pest Management Guide 7-12 Organic Fertilizers Material Guaranteed SOURCES OF Duration Pounds Kg per Analysis NITROGEN (N) per 100 10 m2 (N-P2O5-K2O) Sq. Ft. Alfalfa 3 - 0.5 - 2.4 contains calcium, sulphur, 4 - 6 mo. 5 2.5 Meal/Pellets (or 2 – 1 – 2) magnesium & traces of boron, 1 – 4 mo. manganese, copper and lime; also root stimulant tricontinol; breaks down quickly Blood Meal 12 – 2 - 0.5 moderately fast acting; can burn 3 - 4 mo. 2 1 12 – 0 – 0 plant stems; repels rabbits, deer, 1 - 4 mo. but attracts dogs; slightly acidifying; costly. Canola Meal 8 – 3 - 4 contains nitrogen, phosphorus & 4 - 6 mo 2.5 1.2 trace minerals; fast-acting. Fish Meal 5 – 3 - 5 has major & micronutrients; 6 - 8 mo. 3 1.5 to as high as relatively fast acting; fishy 10 – 6 – 2 odour, relatively inexpensive. Material Guaranteed SOURCES OF Duration Pounds Kg per 2 Analysis PHOSPHORUS (P) per 100 10 m (N-P2O5-K2O) Sq. Ft. Bone Meal 1 - 16 – 0 fast-acting; relatively expensive; 6 - 12 mo. 1 0.5 3 – 15 – 0 promotes root/vegetative 1 – 4 mo. growth Hard Rock 0 - 4 - 0 slow acting; rich in calcium, 5 yrs 2.5 1.2 Phosphate supplies micronutrients/ & iron, fairly inexpensive; soil needs to be pH 5 - 6.5 for uptake by plants Colloidal Rock 0 - 2 - 0 by-product of mining rock 3 - 5 yrs 2.5 1.2 Phosphate phosphate; faster acting, ground up; supplies same nutrients. May contain 20% phosphate but only 2 – 3 % is available. Material Guaranteed SOURCES OF POTASSIUM Duration Pounds Kg per 2 Analysis (K) per 100 10 m (N-P2O5-K2O) Sq. Ft. Greensand 0 – 1 - 6 rich in micronutrients; good soil 5 - 10 yrs 3 1.5 (Glauconite) conditioner for both clay and sandy soils; good for long-term soil improvement; not a fast fix; moderately expensive. Langbeinite 0 - 0 - 22 fast-acting; don't use with 3 - 6 mo. 0.5 0.25 (Sulphate of dolomite lime as you will get too Potash- much magnesium; also supplies Magnesia) sulphur; better for alkaline soils. Wood Ashes 0 – 2 - 7 fast-acting; supplies 2 yrs. 1 0.5 micronutrients; rich source of calcium; will raise soil pH about 2/3 as much as lime; do not use if soil pH is above 6.5; not good for acid-loving plants

Soil Management and Composting - Home and Garden Pest Management Guide 7-13 Material Guaranteed SOURCES OF CALCIUM Duration Pounds Kg per Analysis per 100 10 m2 (N-P2O5-K2O) Sq. Ft. Dolomite Lime 25% Ca; supplies abundant magnesium; 3 - 4 yrs 3 - 7 1.5 – 3.4 8 – 20% Mg raises soil pH. Use lower rates on sandy soil, higher rates on clay. Oyster Shells 34% Ca no Mg; raises soil pH slowly; if 3 - 4 yrs. 3 - 7 1.5-3.4 (Crushed) finely ground dissolves like limestone. Use lower rates on sandy soil, higher rates on clay. Wood Ashes 10 – 30% Ca; fast-acting; supplies 2 yrs. 3.5 1.7 3 – 6 % Mg micronutrients; rich source of calcium; will raise soil pH about 2/3 as much as lime; do not use if soil pH is above 6.5; not good for acid-loving plants; apply 3 weeks before planting the vegetable patch. Material Guaranteed SOURCES OF Duration Pounds Kg per 2 Analysis MICRONUTRIENTS per 100 10 m (N-P2O5-K2O) Sq. Ft. Kelp Meal 2 - 1 – 2 +62 trace vitamins/minerals; immediate to 8 4 (another source increases plant's resistance to 1 month suggests stress; a good soil conditioner; 1 1 – 0 – 4 ) lb dry = 9 lbs fresh seaweed

This table was adapted from the following information by Linda Rehlinger, Master Gardener, B.C. 1. Chapter 2 "Soils and Fertilizers" from the MG Training Manual, written by Craig Cogger, Extension Soil Scientist, Washington State University. 2. "Secrets to Great Soil", by Elizabeth P. Stell 3. 25 kg bag of kelp meal, (Ascophyllum nodosum) by Multi-Crop Industries Inc. 4. Additional reference: Colorado Master Gardener Program Garden Notes #234 revised December 2006, www.cmg.colorado.edu

Soil Management and Composting - Home and Garden Pest Management Guide 7-14 Soil Salinity and Sodicity

The level of soluble salts (i.e., salinity) in Within B.C., naturally-occurring sodic soils the soil is determined in the laboratory by are rare and mostly found in the Peace River measuring its electrical conductivity. region. Salt from road de-icing may also Excessive salt levels in the soil water will cause salinity where runoff water prevent normal growth. Such levels can accumulates. occur naturally and are common in soils in low rainfall areas in the Interior of British Crops vary in their ability to grow in saline Columbia or in areas affected by ocean soils. The following vegetables are best able water spray or intrusion along the coast. to grow in “salty” soils: beet, spinach, Incorporation of organic matter into poorly tomato, broccoli, , cucumber, drained saline soil is a recommended cantaloupe, potato. The least salt-tolerant practice. vegetable is bean.

Excess soil salinity is also found elsewhere in British Columbia, generally caused by over-fertilization, by chemical fertilizers or composts for example. A typical symptom is of excess salinity is lack of growth or plant dieback, or browning of leaf edges after substantial fertilization. In dry areas, the only remedy is to wash, or “leach” the excess salt from the soil root zone with intensive and frequent waterings. In Coastal B.C., tile drainage will allow the excess salts to leach out during the winter rains. During dry weather, sprinkler irrigation may be necessary to grow a good crop in such soils. Prevention of salt buildup by using a sound fertilization program is the most environmentally friendly method to deal with this common problem.

Sodicity refers to the presence of excessive sodium attached to soil particles. The result is poor soil structure, leading to poor drainage and aeration. Applying gypsum helps reclaim sodic soils where sodium levels have become too high. The most economical way is to add gypsum which supplies calcium. The calcium displaces the sodium held on the clay-binding sites. The sodium can then be leached from the soil with low-sodium irrigation water or rainfall.

Soil Management and Composting - Home and Garden Pest Management Guide 7-15