Organic Products S - Z
Sabadilla: A botanical insecticide made from a tropical lily. It is effective on some of the hard-to-kill garden pests such as thrips, cabbage worms, grasshoppers, loopers, leafhoppers, harlequin bugs, adult squash, and cucumber beetles. This is a very toxic organic product that we no longer recommend – which doesn’t matter since it isn’t available anyway.
Sawdust: Sawdust is useful to gardeners primarily as a carbon ingredient for the compost pile. It should be mixed with a nitrogen source when used directly in the soil so it won’t rob the nitrogen from plants. It does not make a good top dressing mulch because it blows and washes away. Well-rotted sawdust is compost and can be used anywhere. One of the best carbon sources for the compost pile.
Seaweed: Best used as a foliar spray. Excellent source of trace minerals. Should be used often. Contains hormones that stimulate root growth and branching. Many trace elements are found in seaweed in the proportions they are found in plants. Seaweed contains hormones and functions as a mild but effective insect control, especially for whiteflies and spider mites. It acts as a chelating agent, making other fertilizers and nutrients more available to the plants. Seaweed or kelp is available in liquid and in dry meals.
Sesame: Sesame is probably the most ancient oilseed known to man. Sesame has been used throughout history in many cultures for many of purposes. For consumption, it has been used to make oil, flour, candy, and is the preparation of wine and brandy. It has been used medicinally for many ailments, including burns, earache, diarrhea, and sores it has been used as a perfume base, as a currency, and as a fuel for lamps. As a natural pesticide, it has been used to repel Tsetse flies in East Africa and control leaf-cutting ants in Brazil. During World War II, patriotic Americans used sesame oil and derivatives from flower petals to ward off pests in their victory gardens. Sesame is considered so safe that it is, in fact, on the FDA’s list of GRAS (Generally Recognized as Safe) materials. Plant residue of sesame tilled into the soil works effectively as a nematocide.
Sewage Sludge: Sewage sludge is human waste. Until recently, most sludge was dumped into the ocean, burned or buried. However, interest is increasing in the use of sludge as a soil amendment. The use of human wastes as fertilizer is ancient and still widely practiced in the Orient. Only since the 1960’s, have various United States cities been marketing processed sludge as a fertilizer. Other cities are making sludge available in bulk to gardeners and farmers for application to agricultural land. There are several forms of sludge available. Some have been activated with beneficial bacteria and others have had little or not treatment. Raw sludge has simply been treated by way of gravity settling. Its major drawbacks are a foul odor and the fact that heavy metals may be present. There is little risk of pathogens if the sludge has been composted. Constant testing is protection from heavy metal contamination. Polluted sludge should not be used on food crops obviously, but non-polluted sludge is an excellent organic fertilizer. Approximate analysis is 3-2-0. Sludge compost is made from city sewage and a high-carbon source such as wood chips or tree trimmings. Most cities should produce this product. Heavy metal contamination is a concern especially for food crops. As long as the heavy metal levels are kept under control, this is an excellent organic soil amendment.
Sheep Manure: Just what it sounds like. As with all animal manures, it should be left on the grazing area soils and as a last resort put into the compost pile.
Sludge: Approximate analysis is 3-2-0. Sludge compost is made from city sewage and a high-carbon source such as wood chips or tree trimmings. Most cities should produce this product. Heavy metal contamination is a concern especially for food crops. As long as the heavy metal levels are kept under control, this is an excellent organic soil amendment.
Soap: Insecticidal soaps are used as organic pesticides to control various small insects. Soaps are non-toxic to people and animals but are indiscriminant on insects and will hurt the beneficials. Commercial products are available or you can make your own by mixing one tablespoon of a non-phosphate soap in a gallon of water. Soap will burn the foliage of some plants like beans, cucumbers and ferns. Water hardness reduces the effectiveness of soaps as pesticides. Soaps should not be used often – they are harmful to beneficial nematodes.
Basically all soaps are biodegradable – some just faster than others. Nonphosphate liquid soaps and water mixed together into a spray are used to control aphids and other small insects. Strong solutions can damage plant foliage, and even weak solutions can kill many of the microscopic beneficial insects and microorganisms – so use sparingly, if at all. Best when used in very small amounts to help make pest control products more effective.
Soft Rock Phosphate: Soft rock phosphate, also known as colloidal phosphate is a clay material that is surface mined from the old settling basins of former hard phosphate rock mining operations in Florida. It contains about 20 percent P205 as well as over 25 percent lime and other trace minerals. It is a very fine material, but can be applied with all common fertilizer spreaders. Natural phosphate stays where it’s put when applied and does not move or dissolve into the soil solution. It needs to be plowed under or tilled into the soil. Unlike chemically made phosphates, soft rock phosphate is insoluble in water, will not leach away, and therefore is long-lasting. Has 18% phosphorous and 15% calcium as well as trace elements. Florida is the primary source. As annual plant takes up to 60 percent of its total phosphates needs the first few weeks of its life. If it doesn’t get phosphate then it is always behind and never catches up. Soft rock phosphate used directly under the seed or transplant at planting time is the very best method of application, especially in low acid or high alkaline soils. It is not as critical but still beneficial in slightly acid to neutral soils. It is almost impossible to overuse soft rock phosphate, you can grow beautiful plants directly in it without any harmful effects.
Soft phosphate rock should be applied at a rate about two tons per acre with other organic amendments. This phosphorous source will soon be gone. It is a byproduct of the making of 0-18-0 and only one company still bags it. In alkaline soils, apply the phosphate directly under the seed or transplants so the small roots don’t have to search for it. This is especially important in the spring. Tests at the Garden-Ville farm have shown that this technique can double production. Unfortunately this product may not longer be available.
Sticky Yellow Trap: Organic growers have been using these traps for years, to monitor and “trap out” whiteflies, fungus gnats, leafminers, flying aphids, leafhoppers, fruit flies and other insects attracted to its bright yellow surface. Cards are coated with a unique non drying sticky substance. Traps must be hung in the immediate area of pest infestation. For trapping out, use 1 trap/25-50 square feet. For monitoring, fewer traps are required.
Straw: Straw is made up of the stalks or stems of farm crops. It is commonly used as a mulch and compost ingredient. To compost large quantities of straw, add nitrogen in the form of green or animal manures to balance the carbon to nitrogen ratio.
Streptomycin: A preventive for fire blight on pears and apples. Use liquid copper during dormant period, and follow-up with streptomycin 2-3 times during the bloom period when temperatures are above 60 degrees and conditions are moist and favorable for infection. Active ingredient is streptomycin sulfate. Approved by some organic certifiers, because fire blight is so devastating and copper should not be used during bloom when infections are likely to start. One pound treats 1/3 to 2/3 acre, makes 100 to 300 gallons. Also good for tomato and pepper bacterial spot.
Sugar: Sugar is a helpful soil amendment used to stimulate microorganisms and to initiate the metabolic processes in the soil. White sugar, when used with other trace minerals in organic fertilizers, is an excellent carbohydrate source. Molasses is an even better form of sugar. For more on the benefits of sugar, read Dr. Arden Anderson’s Science in Agriculture. Sugar should be used on gardens or fields at about 5-10 pounds per 1,000 square feet or less. Some farmers are using small amounts per acre of sugar, humate, and urea. A starting formula for transition to an organic program could be 30-50 pounds of sugar, 50-100 pounds of humate and 50-100 pounds of urea per acre.
Sulfur: Finely ground sulfur is used by mixing with water or dusting on dry plants to control black spot, leaf spot, brown canker, rust, peach leaf curl, powdery mildew, apple scab, and many insect pests. Mix with liquid seaweed to enhance fungicidal properties. Sulfur will also control fleas, mites, thrips, and chiggers. To avoid leaf burn, do not use when temperature is 90 degrees or above. As an insecticide or fungicide use 3 tablespoons per gallon of water. Sulfur is present in oil compounds responsible for the characteristic odors of plants like garlic and onion.
Sulfur deficiency can be distinguished from nitrogen deficiency because the leaves do not completely dry out. Legumes, like alfalfa, have high sulfur requirements, deficiencies usually show up first in these crops. Corn, small grains and grasses rarely show sulfur deficiencies. Since some water contains a high amount of sulfur, watering can sometimes take care of sulfur deficiencies. It takes one pound of sulfur per 100 square feet to lower the pH one point. However, used at this rate, it is very destructive to soil life and beneficial insects. Sulfur has been used as a fungicide for thousands of years. American Indians called it brimstone. Sulfur applications may also damage cucurbits such as squash and cucumbers. Sulfur is a basic mineral often lacking in alkaline soils. Applying granulated sulfur at 5 pounds per 1,000 square feet twice annually can bring base saturation of calcium down and raise magnesium. Be careful not to breathe dust, over apply, or use when planting seed. It can also act as a pre-emergent herbicide. Mix with corn gluten meal and humate for even better results. Sulfur dust is also used as a pesticide in some situations. Sulfur should be used only as a last resort in the orchard. Sulfur and oil sprays should not be used within a month of each other. It is generally classified as a minor element, but it is of major importance to plant growth. Sulfur is easily leached down into the root zone, especially in sandy soils. Therefore, the availability of sulfur will vary considerably during a season, depending on the kind of soil. Add elemental sulfur to the compost pile to speed up the action of microorganisms and the release of nutrients. The rate should be very small, from 0.1 to 0.5% by volume of initial organic material added and related to the nitrogen content.
Sul-Po-Mag: A naturally occurring mineral containing 22% sulfur, 22% potash, and 11.1% magnesium. An excellent product for the organic program. Approximate N-P-K analysis is 0-0-22. Also called Langbeinite and K-Mag, Sul-Po-Mag is mined. Should be applied at 20 pounds per acre as needed.
Sun Spray Ultra-Fine Spray Oil: Horticultural spray oil for killing mites, aphids and other insects on vegetables, fruit trees and ornamentals. Can be applied up to harvest. Mixes 1 part to 25 parts water. This highly refined mineral oil is used on most vegetable, fruit and nut crops as well as flowers and ornamentals as a suffocant and repellent. It is registered for control of adult and egg stages of most insects including mites, scales, aphids, lacebugs, corn earworms, meanly bugs, whitefly, leaf miners, leaf rollers and beetles, etc. It can be applied during the summer as well as dormant seasons, with no reentry delays and minimal effect on beneficials. It is often mixed with insecticidal soap to extend and enhance soap’s effectiveness. Use one to three gallons of Sunspray per 100 gallons of water. Contains 98.8% refined petroleum distillate, 1.2% emulsifier. It can be mixed with baking soda to make an effective fungicide. Do not use if healthy populations of beneficial insects exist.
Superphosphate: The old style super phosphate 0-18-0 or 0-20-0 made by treating rock phosphate with an equal amount of sulfuric acid was a good source of phosphate in low acid or high alkaline soils because it became calcium sulfate and calcium phosphate which are two natural products found in nature. However, little if any is still made. Triple superphosphate (0-46-0) is a more concentrated source of phosphorus. It is made by using phosphoric acid and is extremely destructive to soil fertility. It is so bare that it quickly combines with various trace minerals making them unavoidable to plant roots.
Superthrive: A liquid product made from vitamins and hormones. It is a good supplement for flowering plants. Use at 3 drops per gallon at each watering for best results. It can be mixed with other products.
Surfactant (Wetting Agent): A chemical used to alter pesticide sprays to reduce the surface tension of the liquid, thereby enabling it to spread out more readily over the plant leaf surface. Surfactants are also used to improve the initial wetting of soil. Don’t overuse because surfactants and soaps are hard on beneficial soil organisms.
Sustane: Granulated fertilizers made primarily from composted turkey manure, Sustane has some odor for 24 to 36 hours but has shown excellent soil improvement and reduction of diseases. Approximate analysis is 5-2-4. It is one of the fastest working organic fertilizers. Apply at 20 pounds per 1,000 square feet or 400-800 pounds per acre. 1103 Main St. West, Cannon Falls, MN 55009, 800-352-9245
Tanglefoot: Tree Tanglefoot is a sticky material used to repel insect pests. Spread on the bark of trees to control gypsy moths, canker worms, climbing cutworms, and ants. Made from natural gum resins, castor oil, and vegetable waxes. Do not put all the way around plant trunks – it will girdle and can kill plants. Apply vertical strips or strips or a paper ring.
Tea Tree Oil: Tea tree oil (neem) has therapeutic uses for such common ailments as acne, athlete’s foot, boils, burns, corns, dandruff, gingivitis, insect bites, mouth ulcers and other infections. It’s also used in deodorant, mouthwash and throat lozenges. Tea tree oil, distilled from the leaves of the Neem (Melaleuca alternifolia) tree, has a colorful and fascinating history. The “good oil” as it’s called in Australia, was such a valued commodity during WWII that those producing it were exempt from service. Helps greatly with fleas, can help improve dogs’ skin condition and makes the coat more shiny. Tea Tree Oil Dog Shampoos are available now.
Texas Greensand (Glauconite): Texas greensand is an iron potassium, silicate that is green in color due to the minerals it contains. Greensand is a marine deposit that contains traces of many if not all of the elements which are in seawater. It has been used successfully for enriching soils for over 100 years. Approximate analysis is 0-2-5. This is a natural source of phosphorous, potash, and trace minerals. Texas greensand is different than the glauconite from the New Jersey area. The natural Texas product contains about 19 percent iron and about 2 percent magnesium. Its pH is 8.3, but don’t let that fool you. Use it on all plants for an effective green-up. Research at Garden-Ville farm proved green sand to be better than most iron products in helping plants overcome chlorosis in high pH soils, slightly better than granite sand. The iron supplement that we recommend the least is Ironite because tests have shown that it has high levels of lead and arsenic. The company agrees with the existence of the heavy metals but argues that the risk is slight since the product is in the gallena form and not quickly available. As a soil conditioner Texas greensand can be used at 10-50 pounds per 1000 square feet on lawns or tilled into the soil. It is also an excellent amendment for golf greens and tees. In potting soils it can be used at a rate of 5-20 pounds per cubic yard. In a Garden-Ville research project demonstration an eroded field that was low in organic matter with a pH of 8.3 was tested 66 test plots of peas, peppers and okra grown in each plot. All were fertilized equally with organic fertilizer and then each plot got an additional product. Many of them were iron products. Texas Greensand plot at 150 pounds per 1,000 square feet outperformed all other iron test products in the plants green color and growth. It even beat the iron sulfate plot. The only plots that did as good or even better were the compost plots.
Three Tine Cultivator: Exactly the right tool for heavy surface weeding and cultivation. This cultivator is great for gently working compost into the top few inches of soil. Curved steel tines should be about 2” apart and have flattened, pointed tips, for excellent grabbing and pulling action.
Triple Action 20: Triple Action 20 is a synthetic fungicide but has extremely low toxicity and biodegrades very quickly. It offers good control of fireblight. Use at 1 teaspoon per gallon. Also sold as Cons an 20.
Triple Superphosphate: The old style super phosphate 0-18-0 or 0-20-0 made by treating rock phosphate with an equal amount of sulfuric acid was a good source of phosphate in low acid or high alkaline soils because it became calcium sulfate and calcium phosphate which are two natural products found in nature. However, little if any is still made. Triple superphosphate (0-46-0) is a more concentrated source of phosphorus. It is made by using phosphoric acid and is extremely destructive to soil fertility. It is so bare that it quickly combines with various trace minerals making them unavoidable to plant roots.
Turkey Manure: Turkey manure is a high-nitrogen manure that is an excellent ingredient for compost. It is best to compost before using.
Urea: Urea is a synthetic protein and is the best choice of all the synthetic fertilizers. Microbes accept urea the same as they do urine. It contains 45 percent nitrogen. Natural urea is a waste product from animals. Synthetic urea is the only manmade fertilizer that contains carbon. However, sugar or molasses and humic acid needs to be applied with it to maximize its efficiency. It is made synthetically by reacting ammonia and carbon dioxide under high pressure and temperature. Urea, when used at low levels and in conjunction with organic matter and sugar, is an effective and organically acceptable fertilizer. It helps jump start the microbes. Humates are a good organic matter choice for this use. Large amounts of urea can damage seeds and vegetation can be toxic to aquatic life because of ammonia buildup.
Urine: Natural liquid fertilizer. Fertilization with urine alone can produce impressive growth of grasses and clover much earlier in the spring than other types of feeding. The elements in urine are more quickly available because they are in solution. Urine is also a good activator for converting crop residues to humus.
Vermiculite: Vermiculite can also be used for storing bulbs and winter vegetables, and as a base for floral arrangements. Widely used soil and potting mix amendment and a medium for starting seed and rooting cuttings. Useful for aeration, water retention and improving nutrient exchange. Made from mica rock which is expanded under pressure and heat. It is also used as a potting soil ingredient and as a medium for starting seedlings and rooting cuttings. When vermiculite ore is heated to almost 2,000 degrees F., moisture within it turns to steam and pops the granules to many times their original size. This rapid expansion leaves countless tiny air cells within the mineral. Vermiculite can hold several times its own weight in water but even when the medium is thoroughly wet, ample air circulates about plant roots, helping to avoid damping-off and other diseases. There is some concern about breathing this material.
Vinegar: Vinegar is a wonderful organic tool that was discovered by accident ten thousand years ago when wine was accidentally allowed to ferment too long and turned sour. It can be made from many products, including beer, apples, berries, beets, corn, fruits, grains, honey, malt, maple syrup, melons, molasses, potatoes, rice, sorghum, and other foods containing sugar. Natural sugars from these food products are fermented into alcohol, which is them fermented into vinegar.
The strongest vinegar available for general use is 20 percent or 200 grain, meaning that about 20 percent of the liquid is acetic acid. At this strength, which is corrosive enough to eat metal and must be handled carefully in plastic containers, it will obviously kill weeds, making it an effective nonselective organic herbicide. It works best when sprayed full strength during the heat of the day and in full sunlight. While 200-grain (20 percent) material is the best strength for killing weeds, 100 grain (10 percent), which is made by doubling the amount of water in the 200-grain vinegar, seems to work just about as well if used consistently especially if orange oil is added at about 2 ounces per gallon. Since this diluting process cuts the cost in half, it’s usually advisable to go ahead and use the weaker solution.
If your water is alkaline, add 1 tablespoon of 50-grain (5 percent) natural apple cider vinegar to each gallon of water to improve the quality of the water for potted plants and bedding. This doesn’t have to be done with every watering, though it wouldn’t hurt. This technique is especially helpful when trying to grow acid-loving plants such as gardenias, azaleas, and dogwoods. A tablespoon of vinegar per gallon added to the sprayer when foliar feeding lawns, shrubs, flowers, and trees is also highly beneficial, especially where soil or water is alkaline. The other horticultural use for vinegar is the watering can.
Fruit vinegar is made from the fermentation of a variety of fruits. Apples are most commonly used, but grapes, peaches, berries and other fruits also work. The product label will identify the starting ingredients, such as “apple cider vinegar” or “wine vinegar”. Malt vinegar is made from the fermentation of barley malt or other cereal grains. Sugar vinegar is made from sugar, syrup, or molasses. White, spirit, or distilled vinegar is made by fermenting distilled alcohol. Distilled white vinegar is made from 190 proof alcohol that is fermented by adding sugar and living bacterial. Natural vinegar contains at least fifty trace minerals. Vinegar that is made from the petroleum derivative, 99% acetic acid, is not acceptable in an organic program.
Vitazine: A liquid biostimulant product that is made by Vital-Earth Resources. See Earth-Safe Products.
Volcanite: A blend contains four different volcanic, paramagnetic crushed rocks including zeolite. The zeolite is no longer paramagnetic but it has a very high cation exchange capacity, and since we are low in iron I also added glauconite – a sedimentary mineral rich sandstone commonly called greensand. A blend of several rock materials from the Garden-Ville Company in San Antonio including basalt, lava sand, zeolite, granite, and Texas greensand. This blend works better than any of the ingredients used alone. It’s very economic because only small applications are needed to increase production. Overuse of this material can actually reduce production. Recommended rates are 1000-2000 pounds per acre, or 50 pounds per 1,000 square feet.
Weed Fabrics: Synthetic fabric that supposedly allows air and water movement, while at the same time blocking out some weed growth. For use in all gardening areas and under walkways, driveways, decks, and patios. I don’t recommend it. Use a thick layer of mulch instead in order to maintain the natural processes in the soil.
Wheatbran: Food product that functions as a soil amendment and mild organic fertilizer.
Willow Water: Willow tea water in which willow cuttings have soaked is an effective growth stimulator. You might want to try soaking seeds of woody plants in willow tea before planting. It will not take the place of acid scarification, though. It also works as rooting stimulator for softwood or hardwood cuttings. To make, soak 5 or 6 stems (6”-8” long) in water overnight. Then soak the cuttings in the willow water for an hour or so before putting in the propagation medium.
Wood Ashes: A valuable source of potash. Wood ashes generally contain from 1 to 10 percent potash and 1-1/2 percent phosphorus. They can be mixed with other fertilizing materials or side-dressed around growing plants. Apply about 5 to 10 pounds per 100 square feet. Avoid using wood ashes around blueberries or other acid-loving plants and don’t use heavily in alkaline soils. Only wood ashes, and not coal ashes, should be used in the soil or compost. Wood ashes are also an effective tool in controlling slugs.
Wood Preservatives: Until the mid-1980s wood preservatives containing pentachlorophenol (often called “penta”) arsenates or creosote were widely recommended. However, in 1986 the EPA restricted the use of these materials in response to mounting evidence that all three can cause birth defects and other serious health problems. The debate continues but anyone with sense knows the severe health hazards posed by penta, arsenicals and creosote. Better choices include linseed oil, borax products and naturally resistant woods. There are now several manufactured woods available. They include TREX, Choice-Dek and ….
Worm Composting: Worm composting (or vermicomposting) is a natural and efficient way to “recycle” organic kitchen waste and compost your food scraps indoors with worms, and reduce the volume of your household garbage by as much as 25%. The end result is unsurpassed as an organic soil builder and plant fertilizer.
Yeast: Beneficial soil organisms that exist in healthy soils. Unicellular fungi which convert sugars to alcohol and carbon dioxide. Living yeast cultures are better for animal nutrition, the brewer’s yeast is dead and primarily used as a natural protein source.
Yellow Sticky Traps: Nontoxic, bright-yellow cards that trap insects with their sticky coating. They are primarily used to monitor insect populations. They give some effective control in greenhouses.
Yucca Extract: Yucca extract not only makes sprays stick to crop foliage, it is also a great foliar material itself. It contains complex sugar structures which help plants assimilate nutrients, and develop stress resistance. Use two to three ounces per acre or one-fourth teaspoon per gallon per foliar application, when Therm X70 is applied alone or in combination with other foliar materials. Use a maximum of eight to ten ounces per acre per year. This product foams heavily and should be added last when mixed in high agitation systems. Use at sixteen ounces per acre, once a year. Available from Peaceful Valley Farm Supply.
Zeolite: Zeolite can also be used for air and water purification, cat litter material, shoe deodorizers, animal feed supplements, garage floor spill removers, cooler and refrigerator odor and moisture removers, animal stall odor and moisture removers, and soil amendments. Mix raw zeolite (powder or granular) into the soil for new bed preparation. Broadcast onto contaminated soil to detoxify. Rates can vary from 10- to 50 pounds per 1,000 square feet. More than 50 pounds won’t hurt anything but is probably a waste of money. Zeolite has a very high cation exchange capacity (CEC). It helps fertilizer to be more efficient. A natural ore used to absorb odors, gases, liquids and as an amendment to most soils. Zeolites are natural volcanic minerals with unique characteristics. Their chemical structure classifies them as hydrated aluminosilicates, comprised of hydrogen, oxygen, aluminum, and silicon arranged in an interconnecting lattice structure. Zeolites heave the ability to change and absorb certain harmful or unwanted elements from soil, water and air. An example is the removal of calcium from hard water. Zeolite has a strong affinity for certain heavy metals such as lead and chromium. Zeolite works as a soil amendment by absorbing nutrients, especially nitrogen, and then releasing them at a rate more beneficial to plant root development.
Zinc: Zinc is an important trace mineral and frequently deficient in soils. Zinc is important for the sweet taste in vegetables and fruit. Zinc deficiency can impair growth, delay healing, and contribute to chronic disease. Lack of zinc is common in alkaline soils. However, soil with a high content of organic matter will have a sufficient amount of available zinc. Use of compost, organic fertilizer, aeration and other organic techniques will usually release zinc that is present but not available from the soil. Be very careful when adding zinc. Too much can quickly cause a zinc toxicity. Zinc deficiency results from heavy applications of artificial fertilizer. Large amounts of nitrogen, phosphorus and potassium in the fertilizer tie up available zinc. Low organic matter and soil compaction contribute to lack of available zinc. Deficiency shows in leaves with dead areas, poor bud formation, and small terminal leaves. Weed pressure is greater when zinc is deficient. Not needed in acid soils or balanced soils. Zinc is a trace element found in most organic fertilizers. Zinc is available in manure, rock phosphate, fish, seaweed and compost. Zinc deficiency is characterized by leaves which are abnormally long and narrow, deformed with wavy edges. The leaves may also turn yellow and be mottled with many dead areas. Since zinc deficiency tends to result in iron deficiency, the symptoms of both problems are similar. Zinc deficiency in pecans causes a rosetting of terminal foliage. Zinc locks up at a neutral pH supposedly.
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