soil revitalization

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How to revitalize soil and grow food in any condition. Provides useful techniques for improving soil structure and how to add beneficial bacteria and organic matter to soil. Topics such as structure and water retention are discussed.

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Page 1: Soil Revitalization
Page 2: Soil Revitalization

What Is Soil?What Is Soil?

• What Is Soil Made of?What Is Soil Made of?• Soil TextureSoil Texture• Different Soil TypesDifferent Soil Types

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Definition of SoilDefinition of Soil• This definition is from Soil Taxonomy, second edition.• soil - Soil is a natural body comprised of solids (minerals and organic

matter), liquid, and gases that occurs on the land surface, occupies space, and is characterized by one or both of the following: horizons, or layers, that are distinguishable from the initial material as a result of additions, losses, transfers, and transformations of energy and matter or the ability to support rooted plants in a natural environment.

• The upper limit of soil is the boundary between soil and air, shallow water, live plants, or plant materials that have not begun to decompose. Areas are not considered to have soil if the surface is permanently covered by water too deep (typically more than 2.5 meters) for the growth of rooted plants.

• The lower boundary that separates soil from the nonsoil underneath is most difficult to define. Soil consists of horizons near the Earth's surface that, in contrast to the underlying parent material, have been altered by the interactions of climate, relief, and living organisms over time. Commonly, soil grades at its lower boundary to hard rock or to earthy materials virtually devoid of animals, roots, or other marks of biological activity. For purposes of classification, the lower boundary of soil is arbitrarily set at 200 cm.

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Typical Soil MakeupTypical Soil Makeup

Pore Space (50%)• This may contain air

and/or water

Soil Space (50%)• Organic Matter • Mineral Matter

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The GistThe Gist

• Soil is made up of two basic components: minerals and organic matter. Minerals can be subdivided into three main groups: sand, silt, and clay.

Sand: Minerals that range in size from 0.05mm to 2mm Silt: Minerals that range in size from less than 0.05mm to 0.002mm Clay: Minerals with a diameter less than 0.002mm Minerals greater than 2mm and less than 2m in diameter are known as coarse fragments.

Organic matter is any material present in the soil that was once alive and has been broken down into humus by micro organisms.

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Sand Silt Clay

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Soil Texture

• Determined by the percentages of clay, silt, and sand present in the soil.

• The most important soil characteristicAffects:• Drainage• Water holding capacity• Aeration• Susceptibility to erosion• Organic matter content• Cation exchange capacity (CEC)• pH buffering capacity• Soil tilth

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Sand

• Feels gritty to the touch. Breaks apart easily.• Drains very well, thus has poor water retention.• However, since water drains so well, soil is well aerated.

Organic matter breaks down quickly. • Too Coarse. Soils with lots of sand have big spaces between

the particles; they don't hold water or nutrients. • Sand doesn't react with other chemicals. Intermolecular

attractions are minimal, thus sandy soils don't stick together very well.

• Plant roots can't hold on to this soil. But the big spaces do allow air into the soil. There are some plants that are able to grow in sandy topsoil by putting their roots deep, through the sand to the subsoil.

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Silt

• Somewhere in between sand and clay.• Good water retention. Poor drainage. But more fertile than

sand.• Too Light. This is material which is finer than sand, but still

feels gritty. Silt is commonly found in floodplains and is the soil component that makes mud. Soils with a lot of silt make excellent farm land, but erode easily. This is the soil blown away in dust storms and carried down stream in floods.

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Clay

• Feels sticky when wet. Easily malleable. • Very porous, so it retains water very well; poor drainage.• Low oxygen level in soil so organic matter breaks down

slowly• Too Fine. Lots of clay makes the soil heavy and dense. The

spaces between soil particles are very tiny. When clay soil is dry, it's almost as hard as concrete. Plant roots can't push through it. No air can get in from the surface. Most bacteria and other soil organisms that need oxygen can't breathe. But clay is important because it can change the soil chemistry. Clays give off minerals and absorb acids.

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Identifying Soil Texture by MeasurementIdentifying Soil Texture by Measurement

1. Spread soil on a newspaper to dry. Remove all rocks, trash, roots, etc. Crush lumps and clods.2. Finely pulverize the soil.3. Fill a tall, slender jar (like a quart canning jar) 1/4 full of soil.4. Add water until the just is 3/4 full5. Add a teaspoon of non-foaming dishwasher detergent.6. Put on a tight fitting lid and shake hard for 10 to 15 minutes. This shaking breaks apart the soil aggregates

and separates the soil into individual mineral particles.7. Set the jar where it will not be disturbed for 2-3 days.8. Soil particles will settle out according to size. After 1 minute, mark on the jar the depth of the sand.9. After 2 hours, mark on the jar the depth of the silt.10. When the water clears mark on the jar the clay level. This typically takes 1 to 3 days, but some soils may

take weeks.11. Measure the thickness of the sand, silt, and clay layers.12. Thickness of sand deposit ____13. Thickness of silt deposit ____14. Thickness of clay deposit ____15. Thickness of total deposit ____16. Calculate the percentage of sand, silt, and clay.17. [clay thickness] / total thickness] = ___ percent clay 18. [silt thickness] / total thickness] = ___ percent clay 19. [sand hickness] / [total thickness] = ___ percent sand 20. Turn to the soil texture triangle and look up the soil texture class.

There’s also the feel method.

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What does it all mean?

Different Soil Types

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Soil pHSoil pH

• What is pH?What is pH?• pH and nutrient pH and nutrient

availabilityavailability

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Soil pHSoil pH

• pH is a measure of the acidity or alkalinity of the soil. It is the negative logarithm of the molar concentration of (H3O+) ions.

• A low pH, below 7, means a high concentration of free hydrogen ions (acidic), while a high pH, above 7, means a low concentration of hydronium ions (basic/alkaline).

• Soil pH plays a big part in a plant’s ability to absorb certain nutrients from the soil. A pH between 6.2-7.2 is ideal for most plants.

• Generally speaking, if your plants are growing healthy and well, your pH is probably fine. If your plants are having nutrient problems or are not growing vigorously, it’s worth it to test your pH. If the soil’s pH is not within an acceptable range for the plants you are growing, the plants will not be able to access the nutrients in the soil, no matter how much you feed them.

• You can buy many types of pH testers in a garden center. You can also bring a sample into your local Cooperative Extension office, to be tested for a nominal fee. Once you know what your pH is, you can begin to adjust it slowly. You add some form of lime to raise pH and a form of sulfur to lower it. What type and how much depends upon your soil and test results. Your Extension report and most testing kits will tell you what to do once you get your results.

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Soil pH and Nutrient AvailabilitySoil pH and Nutrient Availability

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Most Plants Like Near-Neutral SoilsMost Plants Like Near-Neutral Soils

~16~

Best forminerals

Best for fungi

Best forbacteria

Most plants

grow in this

range.

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Revitalizing Poor SoilRevitalizing Poor Soil• Organic Matter: The Cure-allOrganic Matter: The Cure-all• Soil BiotaSoil Biota

Amending Specific TypesAmending Specific Types•Light Soil (Sand)Light Soil (Sand)•Heavy Soil (Clay)Heavy Soil (Clay)•Acidic SoilAcidic Soil•Alkaline SoilAlkaline Soil

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GoalsGoals

• The living organisms in and on the soil do most of the gardening. Provide them with a hospitable environment!

• Make sure you soil has a well-balanced nutrient and mineral profile.

• Fix any soil texture or pH problems with amendments.

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Organic Matter:The Cure-all

• “Believe it or not, soil is a delicate substance. More than merely delicate, it is quite literally alive. It is the life of the soil, not its sand and clay, that makes it fertile and productive. A single teaspoon of good garden soil contains millions of microbes, almost every one of which contribute something positive to the garden. The organic matter serves as a pH buffer, detoxifies pollutants, holds moisture, and serves to hold nutrients in a fixed form to keep them from leaching out of the soil.”

• Nutrient SupplyOrganic matter is a reservoir of nutrients that can be released to the soil. Each percent of organic matter in the soil releases 20 to 30 pounds of nitrogen, 4.5 to 6.6 pounds of P2O5, and 2 to 3 pounds of sulfur per year. The nutrient release occurs predominantly in the spring and summer, so summer crops benefit more from organic-matter mineralization than winter crops.

• Water-Holding CapacityOrganic matter behaves somewhat like a sponge, with the ability to absorb and hold up to 90 percent of its weight in water. A great advantage of the water-holding capacity of organic matter is that the matter will release most of the water that it absorbs to plants. In contrast, clay holds great quantities of water, but much of it is unavailable to plants.

• Soil Structure AggregationOrganic matter causes soil to clump and form soil aggregates, which improves soil structure. With better soil structure, permeability (infiltration of water through the soil) improves, in turn improving the soil's ability to take up and hold water.

• Erosion PreventionThis property of organic matter is not widely known. Data used in the universal soil loss equation indicate that increasing soil organic matter from 1 to 3 percent can reduce erosion 20 to 33 percent because of increased water infiltration and stable soil aggregate formation caused by organic matter.

• Serves as a food source for beneficial microorganisms, insects, and worms.

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Sources of Organic Matter:Sources of Organic Matter:CompostCompost

• Compost is the poster child of organic matter. Compost is any kind of decayed organic matter. You can make your own or buy it by the bag or truckload. Finished compost looks like rich soil. It’s dark and crumbly with an earthy smell. By the time the compost cooking process is complete, weed seeds, fungus spores and other undesirable elements that may have gone into your compost bin, should no longer be viable. Compost can be added to your gardens at anytime, either turned into the soil or used as a mulch or top dressing.

• While it is advised that you keep perennial weeds, pesticide treated material and diseased plants out of your compost bin, most every other form of plant material is fair game.

Potential Ingredients for compost include:– Grass clippings– Leaves– Garden Waster (from weeding, deadheading, pruning...)– Vegetable Peels– Sawdust– Straw– Paper

• Can you think of any places where you may be able to acquire these materials for free? Discussion.• See “Things you should know about” page on group site for recipes and instructions.

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Sources of Organic Matter:Sources of Organic Matter:ManureManure

• Manure Aged animal manure is an organic material with an added bonus of soil nutrients. Animal manure must be aged for 6 months to a year, before it is applied to the garden. Fresh manure will burn your plants, may contain bacteria that can cause illness from contact and it stinks. You can add fresh manure to a compost heap and let it age there.

• Cow, sheep and chicken manure are the most popular varieties, but really any herbivores feces will work. The manures to avoid because of their disease potential for humans are: cat, dog, pig and human manures. Though there are composting techniques available that process them into a safe version of organic matter.

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Sources of Organic Matter:Sources of Organic Matter:Green ManureGreen Manure

• Green Manure Green manures are basically cover crops that are grown with the intention of turning them back into the soil. Obviously this would be more useful in the vegetable garden or in a newly created bed where tilling will not harm existing perennial plants.

• Different green manures offer different advantages. Some, like alfalfa, are grown for their deep roots and are used to breakup and loosen compacted soil. The legumes, clover and vetch, have the ability to grab nitrogen from the air and eventually release it into the soil through their roots. If allowed to flower, clover especially is attractive to pollinators and beneficial insects. All green manures will suppress weeds and prevent erosion and nutrient runoff in areas that would otherwise be unplanted. And they all assist with creating good soil structure and food for the microbes, once they are tilled in and begin to decompose.

• Popular choices for green manure include: annual ryegrass. barley, buckwheat, clover, winter wheat and winter rye.

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Sources of Organic Matter:Sources of Organic Matter:VermicompostVermicompost

• Worm composting, or vermiculture, is one of the easiest ways to recycle food waste because it can be done indoors and is ideal for people who live in apartments and do not have a yard. Vermicomposting is the practice of taking your organic waste and turning it into nutrient-rich fertilizer with the help of worms. If you want to be sure to get composting done at a faster rate and have rich, dark soil, then vermicomposting is right for you.

• Vermicompost is more rich in nutrients than the compost from a regular backyard composter. It also performs better as a planting medium than a commercial potting mix with added nutrients. Worm castings, which are produced from vermicomposting, also hold moisture better than plain soil and contain worm mucus which allows for the prevention of nutrients being washed away at first watering.

• The best worms to use in vermiculture are red wigglers or Eisenia foetida. These worms live well in highly populated conditions and they don't burrow. Red wigglers will eat about half of their weight in food a day. That means if you have one pound of worms you can feed them a half pound of food per day. Also, your worm population will double in size about every three months, but they will not overpopulate your worm bin. Red wigglers are self regulating, so they know when there isn't room for more.

• Worm castings, worm poop, black gold or whatever you want to call it, all consists of the same thing: highly concentrated, nutrient-packed fertilizer that you can use for your garden and house plants.

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Soil Biota• In a balanced soil, plants grow in an active and vibrant environment. The mineral content of the soil and its

physical structure are important for their well-being, but it is the life in the earth that powers its cycles and provides its fertility. Without the activities of soil organisms, organic materials would accumulate and litter the soil surface, and there would be no food for plants. The soil biota includes:– Megafauna: size range 20 mm upwards, e.g. moles, rabbits, and rodents.– Macrofauna: size range 2–20 mm, e.g. woodlice, earthworms, beetles, centipedes, slugs, snails, ants, and

harvestmen.– Mesofauna: size range 100 micrometre-2 mm, e.g. tardigrades, mites and springtails.– Microfauna and Microflora: size range 1-100 micrometres, e.g. yeasts, bacteria (commonly actinobacteria),

fungi, protozoa, roundworms, and rotifers.• Of these, bacteria and fungi play key roles in maintaining a healthy soil. They act as decomposers that break

down organic materials to produce detritus (humus) and other breakdown products. Soil detritivores, like earthworms, ingest detritus and decompose it. Saprotrophs, well represented by fungi and bacteria, extract soluble nutrients from delitro.

• Mycorrhizae are specific fungi that form symbiotic associations with plant roots. They improve plant health by enhancing the plant’s ability to tolerate environmental stress (like drought and dry winter weather) and reduce transplant shock. Plants with mycorrhizae may need less fertilizer and may have fewer soil-borne diseases.

• A by-product of mycorrhizal activity is the production of glomalin, a primary compound that improves soil tilth. In simple terms, glomalin glues the tiny clay particles together into larger aggregates, thereby increasing the amount of large pore space, which in turn creates an ideal environment for roots.

• Soil organisms collectively decompose organic matter, resulting in two principal benefits.• First, as soil organisms decompose organic matter, they transform nutrients into mineral forms that plants

can use; thus this process is called mineralization. Without soil microorganisms, insects, and worms feeding on organic matter, the nutrients in organic matter would remain bound in complex organic molecules that plants can’t utilize.

• Second, as soil organisms break down organic matter, their activities help improve soil structure. Improved soil structure provides a better environment for roots, with less soil compaction and better water and air movement. Many gardeners know that organic matter improves soil, but it is important to note that its beneficial properties are only released after being processed by soil organisms

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Nitrogen Cycle of SoilNitrogen Cycle of Soil

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Encouraging Beneficial Encouraging Beneficial MicroorganismsMicroorganisms

• Provide lots of organic matter as a feedstock. Also dried molasses encourages growth.

• Use of compost teas.• Keep soil moist!• While organic matter does also provide a place for the

bacteria and fungi to live, some materials are better than others such as biochar (DO NOT USE IN HIGH pH SOIL).

• Maintain a pH suitable for microorganisms: 6.5 – 7.5• You can use inoculants to jump start their growth, best

used in finished compost and then mixed into soil.• Vermicompost is full of beneficial bacteria and with larger

populations and varieties than ordinary compost.

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Microscopic view of Biochar’s Surface Microscopic view of Biochar’s Surface StructureStructure

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Encouring Beneficial InsectsEncouring Beneficial Insects

• The four main types of beneficial insect you'll want to attract to your garden are:Predatory InsectsParasitic InsectsPollinatorsDecomposers

• When choosing plants, the most important thing to remember is that diversity breeds diversity. The best way to maximize insect diversity is to have a lot of different kinds of plants.

• One of the very best insect-attracting plants is clover.• Other great insect-attracters include members of the carrot family such as dill,

Queen Anne's Lace, and Angelica, scented geraniums, tansy, aster, butterfly weed (Asclepias tuberosa), marigolds, bergamot, daisies, coneflowers, marguerites, sunflowers, thymes, and sages. Weeds such as dandelion and mustard are also popular, as are some agricultual crops, such as alfalfa.

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Creating a Habitat for Beneficial Creating a Habitat for Beneficial InsectsInsects

• Just as important as choosing the right plants, is providing a place for beneficial insects to call home. • Insects prefer a slightly sloppy garden to a perfectly manicured one. Many beneficial insects

overwinter in leaf litter or rotting wood, so creating a small brush pile in one corner of your yard will give them a hand.

• Mulches of wood chips or other organic matter are another way to give many beneficial insects a home, and they also protect soil against early frosts that can kill earthworms before they have time to dig down for the winter. Be careful not to pile mulch too thickly under trees or too close to their trunks - this can harm the tree. Leaving some bare ground will also benefit ground-dwelling native bees and wasps, while sandy soil protected from rain is favored by the ferocious larvae of the ant lion.

• Dense plantings are attractive to many insect species because they protect against wind and rain. Hedgerows containing a diverse mix of shrubs, flowers, grasses, and the occasional tree have long been popular with farmers in Europe and New England, and are experiencing a revival in other parts of America as well, especially among organic farmers and practicers of permaculture and biointensive integrated pest management techniques such as farmscaping. Ground covers can help maintain proper temperatures and humidity levels for some species, such as aphid midges and predatory decollate snails.

• Other beneficial insects, including predatory ground beetles, like to hide under stones, bricks, or fallen logs, or in compost piles.

• A few beneficial insects, especially damselflies and dragonflies, are semi-aquatic. A small water garden will attract them, and also provide a good source of water for other insects and birds

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EarthwormsEarthworms

• The activity of earthworms is most easily appreciated by comparison with the situation in regions where they are absent: the decomposition of organic matter there is slow, such that layers of litter accumulate on the soil surface and fail to be incorporated into the soil. More specifically, the activity of earthworms is important to the agriculturist in four respects, in that they:– improve soil structure– mix and till the soil– aid in humus formation– increase the availability of plant nutrients

• The burrowing of earthworms improves the physical structure of the soil, creating channels through which plant roots may more easily penetrate the soil. In addition to increasing soil porosity and aeration, this activity also improves soil drainage and water penetration while eliminating hardpan conditions. Earthworms may also enhance soil structure through the formation of aggregates. Secretions in earthworm intestines cement soil particles together into aggregates which aid in erosion control. Man, through agricultural practices, such as cultivation, may temporarily improve soil structure, but the earthworm has longer-term effects in maintaining soil tilth.

• As earthworms burrow through the earth, they consume large quantities of soil and fresh or partially decomposed organic matter from the soil surface, depositing it as fecal matter, or casts, in the lower soil horizons. Similarly, soil from the subsoil horizon is moved by these animals to the upper levels where it is mixed with the surface soil, resulting in a more uniform distribution of plant nutrients. Charles Darwin (1881), the naturalist famous for his ideas on evolution, estimated that 10.6 tons of materials are brought to the soil surface of each acre by earthworms (or approximately St/hectare).

• Through the ingestion of organic matter earthworms are important to the initial breakdown as well as to subsequent decomposition of organic matter. In fact, earthworms may consume more surface organic matter than all other soil animals together. This material is eventually excreted as casts, concentrating nutrients and rendering them more water-soluble and available to plants. Researchers have found that worm casts are generally richer in exchangeable calcium, potassium, and phosphorus than the surrounding soil, while earthworms themselves and their excretions are valuable sources of nitrogen. By bringing soil nutrients to the upper horizons from the lower subsoil, the earthworms counteract the effects of leaching whereby many nutrients are washed from the root zone and consequently rendered unavailable to plants.

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EarthwormsEarthworms

• How to Encourage Earthworm Activity– Earthworms will not go where it is too hot/cold or too dry/wet. Soil temperatures above 70º F or

below 40º F will discourage earthworm activity. While soil temperature is hard to alter, moisture can be managed. When soil becomes water logged, oxygen is driven out of the large pore spaces. Without this free oxygen, earthworms cannot breath. Conversely, when soil dries beyond half of field capacity, earthworm skin dries in the soil. Maintaining moisture levels that are ideal for optimum plant growth in a landscape or garden will also be ideal for earthworm activity.

– Providing a food source in the form of organic matter is also important. Mulching grass clippings into the lawn, putting down a layer of organic mulch in beds, amending the soil with compost, and turning under a green manure are all excellent ways to feed earthworm populations.

• Practices Detrimental to Earthworm Activity– High rates of ammonium nitrate are harmful to earthworms– Tillage destroys permanent burrows and can cut and kill worms. Fall tillage can be especially

destructive to earthworm populations. Deep and frequent tillage can reduce earthworm populations by as much as 90%.

– Earthworms are also hindered by salty conditions in the soil.– Some chemicals have toxic effects on earthworm populations.

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Sandy Soil (Light Soil)Sandy Soil (Light Soil)

• Problem: Soil drains too fast, requires lots of water. Sandy soil has low levels of beneficial nutrients since they are washed away every time water passes through.

• Solution: Add material that will act as a sponge to hold water and nutrients. Also, add materials to provide the nutrients.• What you can use: With sandy soil, you should add LOTS of organic compost. Other amendments include manures, topsoil,

kelp meal, coconut coir, expanded shale. All amendments should be mixed in at least 8-10 inches down.

• Increasing soil organic matter is the key to gardening in sandy soil. You have to make the soil more “sticky”, so water and nutrients don’t just flush through every time it rains.

• You do this by making the soil more hospitable to bacteria. Bacteria will provide the glue to bind your sandy soil into something much better.

• Garden Compost is the Best Form of Organic Matter to Add• Bacteria need moisture and nutrients to multiply. Both are in short supply when gardening in sandy soil. Good garden

compost is loaded with diverse populations of active and dormant bacteria and beneficial fungi, as well as residual bacterial “glues” that help bind sand particles together, while soaking up and holding moisture.

• You can add large amounts of good, balanced compost when gardening in sandy soil, up to 40% of the soil volume. This will give you a marked improvement in both water retention and crop yield in the first season, with continued improvement in subsequent seasons.

• Coir Accelerates the Process• Coir is dried, compressed coconut husk. A cheap and abundant biproduct of the coconut industry, it comes in brick-sized to

suitcase-sized blocks. • Coir is an ideal soil amendment for gardening in sandy soil. It soaks up 5 times it’s weight in water, and holds it in the soil

for a long time. It’s slightly acidic, just the right pH for most fruits and vegetables. Composed mostly of lignins, it breaks down very slowly, and can improve water retention when gardening in sandy soil for as long as 8 years.

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Clay Soil (Heavy Soil)Clay Soil (Heavy Soil)

• Problem: Does not drain well. Soil is poorly aerated and inhospitable for aerobic bacteria. Roots are smothered.

• Solution: Use materials that help clay clump together creating spaces for water and air to pass freely through the soil.

• What you can use: LOTS of organic matter and expanded shale. Though some people recommend using a coarse sand and organic matter, it is a dangerous practice that can result in a concrete-like soil texture. Coconut coir is also a good amendment especially in alkaline soil (which most clay is).

• The master gardeners at Texas A & M recommend laying down 3” of expanded shale and 3” of organic compost. The amendments are then tilled in 8 – 10” down into the soil.

• See “Things You Should Know About” page for details.

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Adjusting pHAdjusting pH

• Discuss organic matter.

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Raising Soil pHRaising Soil pH

Amendments include:•Agricultural limestone-- This is the product most often used. It can be purchased at farm and garden stores or farm feed stores, etc. Agricultural limestone has a much less potential for burning than other lime products. It comes in small pellet form or ground (almost powder) form. •Dolomitic Limestone-- Dolomitic limestone contains magnesium. This is a great product for acidic soil that is also low in Magnesium. Here you knock out two birds with one stone. Neutralize hydrogen and restore Mg levels are well. •Hydrated limestone- Hydrated lime is what is used in mortar or cement products. It is sometimes used on lawns because it works slightly faster, but has a much greater burn potential. Hydrated lime should not be used on Centipede grass or other grasses sensitive to lime. When using hydrated limestone, it should only be used in small amounts in the cooler parts of the year. Be sure to water it in.•Wood ashes-- Wood ashes are only 40 percent as effective as limestone, but may be a good choice when only a slight correction is needed. However, be careful about using your garden as a place to dump ashes throughout the winter. Some gardens have recorded the soil pH as high as 11. It can take several years to restore the pH back to neutral. •Organic matter- Most composted organic matter will be neutral to slightly alkaline. If the soil needs only a slight correction, simply applying organic matter may be all that in needed. This is especially helpful in garden areas where larger amounts of organic matter is tilled into the soil.•Biochar – biochar can have pH as high as 12-13 depending on the ash content, thus making it a good amendment for acidic soil. It also increases soil microbe activity, improving the fertility of the soil.

•Note 1: Limestone is slow to break down and is best if it can roto-tilled into the soil, when possible. When broadcasted over the grass surface, the smallest limestone particles will work into the soil faster than larger particles. While powdered limestone is much messier to work with, it will alter the pH faster.•Note 2: The purity of the lime product varies with the manufacturer. Products are rated for purity using a Calcium Carbonate Equivalent (CCE) rating. A rating of CCE 100 is pure, but cheaper products may be as low a CCE 60. If you use a cheaper product you will have to use more to get the same results of a CCE 100 product.

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Lowering Soil pHLowering Soil pH

Amendments include: •Elemental Sulfur: If dramatic shifts such as a pH 6.5 to 4.5 for blueberries are needed, then elemental sulfur is a better choice. It has more acidifying capability than the other products and lasts for years. However it reacts slowly and may take several months. Soil bacteria convert the sulfur to sulfuric acid. Since it is a biological process it is slower than a chemical reaction. The process occurs when the bacteria are most active in moist warm soil and are not active in the winter. Spring application and incorporation work best. Once plants are planted it's difficult to add much sulfur. Prepare beds in advance; ideally the season before planting.•Aluminum Sulfate: This is the product most professionals use because it works immediately. Aluminum sulfate will change the soil pH instantly because the aluminum produces the acidity as soon as it dissolves in the soil. However aluminum sulfate should be reserved for use only with hydrangeas to promote blue flowers. Aluminum is necessary for the flower color change in hydrangeas but can cause aluminum toxicity in other plants such as blueberries. Many acres of land in the world are unusable for crops due to soil acidity and aluminum toxicity. Simply lowering the soil pH with any product will help hydrangeas flowers to be blue but the competitive deep blue will require aluminum sulfate additions. •Iron sulfate can be used to lower pH but requires six times more product than elemental sulfur. It reacts faster at 3-4 weeks than elemental sulfur but as with all the products can cause plant damage if over used.•See this link for using low pH irrigation: http://www.verdegaalbrothers.com/ph_meters/Uses_of_sulfuric_acid_as_water_admendment.pdf

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A Warning for Calcareous SoilIf the soil is calcareous (contains free calcium carbonate), additional sulfur will be required to neutralize the free calcium carbonate. To neutralize a soil that contains 2% calcium carbonate, for example, requires 6 tons of sulfur per acre (this only neutralizes the calcium carbonate; additional sulfur will be needed to affect a change in soil pH). Obviously, it would be impractical to apply enough elemental sulfur to alter soil pH of calcareous soils on a field scale.

The Edwards Plateau is characterized by hilly limestone features. The area soils are generally calcareous and have a high pH. However the soils varies from the dark clay Blackland Prairie to the light sand Post Oak Savannah. More specific soil information can be obtained from the Natural Resource Conservation Service.

Not that you should lose all hope, you should just know what you’re up against. Raised beds (including wicking worm beds) and container garden are very good alternatives to a traditional garden as you have full control over the soil structure.

http://edis.ifas.ufl.edu/ch086

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The Importance of MulchingThe Importance of Mulching

• Organic mulch (including chopped leaves, compost, shredded newspaper, grass clippings, hay or straw) improves the soil as it decomposes, conserves water, increases humidity around plants, reduces weeds and encourages beneficial microbes in the soil.

• Be sure to apply mulch at least 2 inches deep. Plastic sheeting has been shown highly effective at retaining moisture and increasing soil temperatures in the spring. Install irrigation before you apply mulch to cut down evaporation.

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gardening/dry-climate-growing-2.aspxgardening/dry-climate-growing-2.aspx• http://ohioline.osu.edu/agf-fact/0507.htmlhttp://ohioline.osu.edu/agf-fact/0507.html• http://web.extension.illinois.edu/cfiv/homeowners/080818.htmlhttp://web.extension.illinois.edu/cfiv/homeowners/080818.html• http://www.lawn-care-academy.com/soil-pH.htmlhttp://www.lawn-care-academy.com/soil-pH.html• http://tinyurl.com/3g79qbbhttp://tinyurl.com/3g79qbb• http://www.verdegaalbrothers.com/ph_meters/http://www.verdegaalbrothers.com/ph_meters/

Uses_of_sulfuric_acid_as_water_admendment.pdfUses_of_sulfuric_acid_as_water_admendment.pdf