Soil in the Massachusetts School Garden

Taking care of your soil is perhaps the most important factor in your school garden. This how-to guide includes a background on soil formation, and then six different tests that you can conduct with children to analyze and understand your garden soil. This is followed by six techniques you can use to improve your soil based on those findings.

Background: Soil Formation

The soil is a mixture of living and non-living components, organic and mineral. It is formed through the action of parent material, climate, plant, insect and animal life, in different topographical locations over time. The relative influence of each of these factors differs in different locations.

Parent Materials are the minerals that break down to form soil. Much of this is from hard rocks such as granite. These parent materials may be derived from the bedrock that is directly below a soil, or the soil may be composed of an entirely different mineral that has been transported from a different location. In this case, glaciers may have moved rock fragments and earthy materials, or the minerals may have been deposited by water as sediment along rivers and streams, in the flooded bottomland of existing streams, out of the still water of historic lakes or deposited by tides from the sea. Wind and gravity can also move soil.

The kind of climate under which a soil forms largely determines the nature and the rate of physical and chemical weathering of these parent materials. Wind or rain may weather rock surfaces, breaking down the rock and adding those minerals to the soils. Cold wet winter temperatures cause frost action, which also breaks apart rock fragments.

Soil in the Massachusetts School Garden - Massachusetts Agriculture in the Classroom 2012

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Soil in your Massachusetts School Garden

Insert 1.Massachusetts Soils

Massachusetts was covered with glacial ice 12,000 to 14,000 years ago. The parent material of the most extensive soils in our state are comprised of various types of glacial deposits. These soils have weathered little compared to soils in non-glaciated areas and have developed relatively weak soil profiles.

Some Massachusetts soils were deposited beneath advancing or retreating glaciers. These are dense, firm sandy loams. Other soil were deposited by melting ice. These tend to be coarsely textured, sand, gravel and stones. Post glacial winds deposited 1 to 2.5 feet of silt or very fine sand over glacial sediment in many areas of Northern Massachusetts.

Along major stream valleys, glacial outwash deposits consisting of layered sand and gravel overlain by a more weathered, loamy or sandy surface layer and subsoil may be found. Low plains were formed along parts of the present coast of Massachusetts when ocean levels receded following glaciation and marine

Glaciation grinds and moves even large rocks. Rainfall can leach water-soluble minerals down through the soil. Climate also affects the type of vegetation in an area, which affects those soil-forming processes related to plant life.

The topography or shape of the land surface, slope and the position of the soil on the landscape are dominant factors in soil formation. Soils that formed in identical parent materials and under the same conditions vary because of position on the landscape. This is largely the result of drainage conditions caused by differences in surface runoff or depth to the seasonal high water table in that location.

Soils formed at higher elevations and in sloping areas generally are well drained, with six feet or more depth to ground water. Surface runoff is rapid. In these areas, soil colors are bright strong brown to yellowish brown in the subsoil grading to a lighter, grayer unweathered substratum.

On soils at lower elevations, such as those in swales, adjacent to drainage ways and water bodies, and in depressions, surface runoff typically flows down from higher elevations. The seasonal high water table is often at a shallow depth. In these areas the soils are somewhat poorly drained and generally have a yellowish brown color with gray subsoil. In poorly and very poorly drained soils, the seasonal high water table is at or near the


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sediments were left exposed. The sediments generally are at elevations as high as 50 feet above sea level and grade gently to sea level.

Moderate temperatures in Massachusetts allow the accumulation of organic matter in the surface layer of most soils. Rainfall leaches water-soluble minerals down through the soil, resulting in acid soil throughout most of the state. In winter, cold temperatures and high moisture cause frost action, which is especially active in loamy soils not under forest vegetation. Frost action breaks apart rock fragments, and in some soils influences soil structure.

Human activities have significantly altered soil in some areas. Many soils have a distinct plow layer formed by mechanical cultivation and additions of organic matter, lime, fertilizer. Some naturally wet soils have been altered by artificial drainage and filing. Throughout the state, especially in urban areas, there are many areas where the natural soil has been covered, removed or replaced by homes, businesses, recreation and other human activity.

Looking to the future of Massachusetts soils, soil organic matter is one of the major pools of carbon in the biosphere and is important both as a driver of climatic change and as a response variable to climate change, capable of acting both as a source and sink of carbon. Soils also helps regulate other greenhouse gases such as nitrous oxide and methane.

Photo: Author. Peck School Holyoke MA 2012

surface for pro-longed periods. The soil profile typically has a dark colored organic or organic rich layer and a strongly mottled or gray subsoil and substratum.

The last element in soil formation is time. It can take as long as five hundred years to make one inch of soil. The soils of Massachusetts are relatively young and have weathered little compared to soils in non-glaciated areas.

Tests For Your Soil

Understanding the soil conditions at your school will help you to understand how to work toward healthy soil in your garden. Determining the specific mineral and organic matter make up determined by soil tests and visual analysis is helpful. In addition, some basic techniques such as adding compost and mulching, are a good idea for any Massachusetts soil and will generally be enough to improve a small non-commercial plot.

In addition, finding out the history of your site and determining any hazards like underground utility lines is important, and figuring out if your soil is contaminated with heavy metals such as lead, is a required step before creating your school garden.

Test 1: Determine Your Soil Type on a Soil Map

No two soils are exactly the same. Over 18,000 types have been classified so far in the U.S. These are divided into twelve major orders with suborders, great groups and families, similar to the taxonomic system used for plants and animals.

There are five main soil types: clay, silt, sand, limestone and peat. Most soils are a mixture, and their description refers to their major constituent. Soil mixtures are know as loams: e.g. a soil with a high proportion of sand could be a “sandy loam”

Go to the website of the USDA’s web soil survey (http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm) to see a soil map of your area and find out your soil type. There are instructions on the first page, but I suggest the following order to make things easier.

On the first page, click the green button that says “Start WSS.” When you get to the next page, in the “area of interest” tab, I suggest you click on “soil survey area” and choose Massachusetts and your county. Next click the “scale” button

above the large box where the map will appear, this automatically calibrates the scale. Once a map appears in the large box, you can then click the “Soil Map” tab, and explore your specific location within this by selecting smaller areas with the zoom button and moving the map around with the “hand” button. Be patient, this program is processing a huge amount of data and can be slow. Once you have found your particular location, you can cross reference the numbers on the map with the soil type in the side bar to determine your soil type. Clicking here on your soil type will tell you more information such as typical drainage properties, parent materials and typical profile. It can be interesting to compare this information with what you find with the hands on tests below.


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http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm




Test 2: Look at Your Soil Profile (also called soil horizons)

Soil has three layers. Topsoil, subsoil and bedrock.

Topsoil (also known as the A horizon) is composed of organic matter and mineral matter that formed at the surface. Most nutrients, organisms and plant roots are located in this layer. A typical topsoil may contain forty-five percent minerals, twenty five percent air, twenty five percent water and five percent organic matter.

The Subsoil layer (also known as the B horizon) contains minerals that are usually weathered from the original parent material. It is often found about one foot below the surface. Deeper tree roots and earthworms live here.

The Parent Material is the bottom layer, as much as three feet below the surface in the Northeast. It is more compact and often has stones and rocks in it.

- Dig a pit with straight sides to a depth of two feet, or until you hit an impenetrable rock layer. (If this is too hard, consider getting help from other adults)


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Top Soil

Sub Soil

Parent Material

- Use a tape measure to measure the depth of the different layers. This will be more obvious in some places than others, but can usually be determined by changes in color.

- Record and diagram your soil layers

How does this help you with your soil improvement plan?

If you have a thin top soil layer, one of you priorities will be to build soil up to a level that can support plants. If your parent material is close to the surface, you may also need to consider growing more shallow rooted crops until you have built up the soil in your beds.

Test 3: Look at Your Soil Color

Soil color has little known direct influence on the functioning of the soil, but important soil characteristics can be inferred from color. The two major coloring agents are organic matter and iron. Organic matter darkens the soil: as little as 2 to 5 percent can give soil a dark brown to black color. These darker soils are generally considered to be better and more fertile. Oxidized iron generally makes the soil yellow to reddish in color, which indicates a well aerated soil, reduced iron makes the soil gray or bluish-green, indicating that it is poorly drained.

Soil color has a sophisticated classification system in soil science using the Munsell color chart and distinguishes soils by hue: red, yellow, green, blue and purple, value: degree of lightness or darkness, and chroma: strength of color. These soil color charts offer 245 different color chips systematically arranged. This level of analysis is generally not necessary for a small garden, but looking at color can give you a quick method of determining soil quality when siting your school garden.


From soil color your can get a sense of the level of organic matter in your soil, and how high a priority adding organic matter is in your soil improvement plan. It can also help you determine how well drained your garden is.

Test 4: Determine Your Soil Texture

Soil texture refers to the relative proportions of sand, silt and clay in the soil. Sands are the largest particles and clays are the smallest. Imagine a piece of sand as the size of a basketball. That would make silt the size of a baseball and clay smaller than the size of a marble. The basic soil textures are sand, loamy sand, loam, silt, silt loam, sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay and clay.

Sand particles can be seen with the naked eye and feel gritty. They can be wiped clean from one’s hands with ease leaving no materials in the pores and fingerprints. They can be further subdivided into size fractions. The classes of sand are coarse sand, fine sand, and very fine sand.

Silt particles can be seen with a hand lens or light microscope. They have a smooth powdery feel when dry, and a slick creamy feel when moist or wet. Some liken the feel to that of talcum powder. Silt is not sticky or plastic. After handling silty soil, a coating will be left on the hand, which for the most part can be brushed off when dry leaving silt particles in the pores and grooves of your fingerprints.


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Clay particles can be seen only with an electron microscope. Clay is sticky and plastic when wet. It is hard when dry. After handling clayey soils a film will be left on the hands, the removal of which requires vigorous washing.

About one half of any soil is made up of pores full of air and water. Plant roots need oxygen from the air in soil for best root development and growth. Many bacteria also need air.

Plants need water to grow. Water movement in the soil brings better air circulation. When water enters the soil, air moves out and is replaced by fresher air as soon as the soil pores are again free of water.


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Photo: Author

Insert 3 Size Classification of Soil Separates

Soil Separate Size

Very coarsesand

2.0 - 1.0 mm

Coarse sand 1.0 - 0.5 mm

Medium sand 0.5 - 0.25 mm

Fine sand 0.25 - 0.10 mm

Very fine sand 0.10 - 0.05 mm

Silt 0.05-0.002 mm

Clay Less than 0.002mm

Gravel 2 mm to 3inches

Cobbles 3 to 10 inches

Stones 10 inches to 2.5feet

Boulders greater than 2.5feet

The amount of open space between soil particles has a lot to do with how easily water moves through a soil and how much water it will hold. Sandy soils do not hold much moisture since there is less surface area for the water to cling to, and there are large pores spaces where the weight of the water causes much of it to run down and out of the soil.

Finer textured soil can hold more water for plants because there is more surface area on which water adheres. Since the size of the pores is reduced, the weight of the water is less and it doesn’t run out of the soil so readily. There is however a fine line. Some soils that are high in clay hold a great deal of water, but hold it so tightly that many plants can not extract the moisture. In general, silt loam soils have the greatest available moisture holding capacity for plant growth.

Compaction: In compacted soils, the particles that make up the soil are pressed together. Not only is the soil physically harder, but without air spaces, a root cannot grow or even breathe. These compacted areas may also be lower than surrounding soils. Not only are the soils squished and compacted, but some of the topsoil may wash away, because plants are no longer there to hold the soil in place. The areas near human habitats are full of examples of compacted and overused land. The land near public building or suburban lawns is often heavily used by people.

- Take a soil sample of about 2 cups from your garden

- Crush any lumps and remove large rocks, sticks or trash

- Take a quart jar and put the soil into it, add water until the jar is 3/4 full

- Screw on the lid tightly and shake vigorously

- Let the jar stand for several minutes.

- You will see that the mixture separates into layers.

The larger particles, such as coarse sand or rocks, will settle to the bottom of the jar. The finer particles of silt and clay will form the next layer. The material left floating on the top of the water is organic matter.


Soil texture determines how well drained your soil is. If you have poorly drained or too well drained soil, you may want to consider adding organic matter such as compost or another soil conditioner.

Test 5: Soil Nutrients and PH.

The bulk of the materials used by the plant to build its own food are hydrogen and oxygen from water and carbon from carbon dioxide. It also needs in small amounts: nitrogen, phosphorus, potassium, calcium, magnesium, iron, and sulfur and in minute amounts boron, manganese, zinc, copper and molybdenum. Soil PH affects which crops will do well in your garden. Unless you are planning to grow a crop like blueberries, which prefers an acid PH, maintaining a balanced PH of in the neutral range around 7.0 is preferred by most plants.


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Nitrogen keeps the leaves green and helps stems grow. Too little nitrogen causes stunted growth and yellow leaves. Too much nitrogen will cause the plant to grow too fast, have poor fruiting, and have weak, soft stems.

Phosphorus helps plants store and use energy from the sun to make food for themselves. Phosphorus is important for beautiful flowers, seed development and general good growth. A phosphorus deficiency causes small, thin immature plants. Plants need large amounts of phosphorus as they begin to grow and when the weather turns cold.

Potassium makes plants stronger, the fruit stays fresher and the grasses greener. Potassium keeps the cells of the plant strong, forming strong stems and roots. It permits free flow of food through the plant, produces starches, controls root growth and open and closes pores for water. Potassium help plants survive droughts, diseases, and very hot and cold temperatures. Potassium is found in the soil but only a small amount is available to plants.

A soil test can help you determine the ratios of these things in your soil, as well as giving you your soil PH and lead content. The University of Massachusetts has a soil testing lab which can be found at http://www.umass.edu/soiltest/. Ask for their basic test. On the second page of the soil test submission form there are detailed instructions on how to take a soil test. Make sure you also specifically test at the drip line of your building if you plan to grow crops there, as this may be a site of accumulated lead.


Although compost is always recommended for any soil nutrient make-up, with the findings from a soil test you can also determine which nutrients to look for in soil amendments and fertilizers, and how much compost you may need to add. It is also vital in determining lead content.

Test 6: Your Soil Food Web

A spoonful of soil contains more microorganisms than there are people on Earth! The soil food web is the exchange of energy between different organisms that live on or from the soil. Many different organisms make up the soil food web, from one-celled bacteria, algae, fungi, and protozoa, to the more complex nematodes and micro-arthropods, to earthworms and insects.

The plants, lichens, moss, photosynthetic bacteria, and algae that use the sun’s energy to fix carbon dioxide from the atmosphere. Most other soil organisms get energy and carbon by consuming the organic compounds found in plants, other organisms, and waste by-products. A few bacteria, called chemoautotrophs, get energy from nitrogen, sulfur, or iron compounds rather than carbon compounds or the sun.


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Insert 4Using Weeds as Indicators of

Soil Conditions From:Weeds and What They Tell, by Ehrenfried Pfeiffer

Weeds Soil Condition indicated

Sorrel, dock, horsetail

Soil is acidic or increasing in acidity

Sweet peas, clover, other leguminous weeds

Soil is sandy or alkaline, too well drained, or needs nitrogen

Wild lettuce, lemon balm, cleavers, chickweed, plantain

Indicates a balanced PH, soil is well drained and fertile.

http://www.umass.edu/soiltest/

http://www.umass.edu/soiltest/

As organisms decompose complex materials, or consume other organisms, nutrients are converted from one form to another, and are made available to plants and to other soil organisms. All plants – grass, trees, shrubs, agricultural crops – depend on the food web for their nutrition.

- Collect in a plastic bag a sample of soil and leaf litter from a depth of four to six inches underground. The sample should be moist, since there isn’t much life in dry soil and leaves.

-Place a piece of wire mesh (½ inch holes) inside a funnel and rest the funnel inside an empty coffee can. Put the soil sample on top of the wire mesh.

-Hang a light bulb over the can. Shine the light directly on the soil. The heat from the lamp will drive the soil critters deeper as they look for moisture. They will land in the bottom of the can.

-Dumping the can onto a large sheet of white paper or a tray will allow you to see what is living in the soil.

Note: Also living in the soil are animals as large as woodchucks. Moles, voles and other mammals are a few of the soil’s inhabitants. Some of these larger animals, mix the soil and change its physical characteristics. As these animals burrow and tunnel, they mix the soil, allowing air and water to penetrate beneath the ground’s surface. Their waste products help to aggregate soil particles, improve soil structure, and conserve nutrients in a less mobile state.


Healthy, living soils have a healthy active food web. Soil organisms decompose organic materials in the garden, including manure and compost. They fix nitrogen from the atmosphere, making it available to plants. Many organisms enhance the water holding capacity of soil by building organic matter. Soil organisms prey on crop pests and are food for above-ground animals. If your soil does not have these things, it is an indication of compaction, low organic matter or other soil problems.


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Test 7: Identify any Buried Utility Lines in your School Yard Soil

Before digging in settings near buildings, especially if making deep in-ground beds, you should make sure you will not hit any underground utility lines. “Dig Safe” is a program funded by utility companies. When you call Dig Safe, they then notify relevant utility companies who will come and flag out the location of any buried utility lines.

-Stake out the areas you intend to dig

- Call 1-888-DIG SAFE at least three days before digging.

Insert 5 Macro-invertebrates you might find in healthy soil

Earthworms: Segmented soil critters without legs that move by expanding and contracting their bodies like an accordion. As earthworms eat, they break down plant materials into smaller pieces, aerate the soil, and add nutrients in the form of castings (soil and nutrient-rich wastes that have been digested and released).

Centipedes: Predatory soil critters that move about quickly on many legs. Their bodies are flattened and each body segment has only one set of legs. (Centipedes bite)

Millipedes: Long, rounded soil critters that have hard segmented bodies with many legs. Each body segment has two pairs of legs. As vegetarians, millipedes eat holes in fallen leaves and other things, thus enabling smaller decomposers to continue the decay process.

Springtails: These soil critters literally spring to life when approached. A pointed projection folded inward at the tip of their abdomens can be quickly extended, acting like a spring to propel them into the air. Springtails feed on fungi and other molds, bacteria and decaying matter.

Mites: These very small soil critters look like minute dots moving about in the soil. There are thousands of species and they range in color from white to bright red. Mites are related to spiders and have eight legs and a round body. They eat fungi, other molds and decaying wood and leaves.

Isopods: These soil critters are covered with flattened plates of armor, resembling tiny armadillos. They are brown or gray in color. Isopods eat decaying leaves and wood and are often found in damp leaf litter and rotting wood. They are commonly called Sowbugs or, if they roll into balls when disturbed, Pillbugs.


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Techniques for Amending and Building Soil in Your Garden

1. Composting

As composting is such an important technique we have devoted an entire “How-To Guide” to it, and will not cover it here. While not a cure-all, the addition of compost can help with most soil needs, and if there is a single thing you you should do for your garden soil, it is to add compost! Compost can enrich the soil with nutrients, increase moisture retention, improve soil structure and provide a good environment for beneficial soil organisms. Adding a healthy amount of compost, at least 1” a year to your garden may make all of our other recommendations unnecessary!

2. Cover Cropping

Planting grasses and other plants you don’t intend to use directly for food in your garden has valuable benefits. These benefits include their functions as a “cover crop” - protecting the soil from erosion and compaction, and to out-compete weeds in a dormant bed. They can also function as a “green manure” when these plants are incorporated into the soil to increase fertility or organic matter content. Finally, these plants can be used as a “living mulch,” when under-se eded with vegetable crops, keeping out weeds, keeping the soil cool and preventing erosion. Although these plants can serve all of these functions and more, they are most commonly referred to as cover crops.

A typical time to cover-crop is in the fall, to prepare for the winter, when you have taken your seasonal crops out of your beds. You can then dig in the crop in the early spring to prepare your soil, a few weeks before you begin planting your vegetables if your soil is dry enough to work. If it is too wet and you would compact your soil by working it, consider adding these plants to the compost heap instead.

Insert 6Three Cover Crop Combinations for the School Garden

Crop When to Sow

Use

Winter Rye/ Hairy Vetch Fall A good winter cover crop combination. The vetch, a legume (like a pea or bean) captures nitrogen for spring vegetable crops.

Red Clover/ Oats Spring A good quick growing combination that can be tilled in for a fall garden. Red clover has good phosphorous accumulation.

Buckwheat/ Soybeans Spring The buckwheat is fast growing and accumulates phosphorus, the soybeans nitrogen. Good as a part of a crop rotation and the soy beans may be harvested.

(adapted from : “Green Manures for Home Gardens” in the Rodale Encyclopedia of Organic Gardening (see sources))


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http://www.aginclassroom.org/For%20Educators/Gardening_Resources/How-To-Guides_For_School%20Gardening/Composting.htm

http://www.aginclassroom.org/For%20Educators/Gardening_Resources/How-To-Guides_For_School%20Gardening/Composting.htm

How to plant a cover crop :

• Choose a cover crop for your garden, taking into consideration its intended use, and time of year. (See Insert 6 for some options.)

• Remove all crops residues from your beds, level and rake the bed free of lumps.

• Scatter the seed as evenly as possible by hand. (Try to get kids to hold it palm up and to make circular motions with their hand to scatter it. This helps avoid all the seed landing in a clump in one corner of the bed!)

• Tamp all over the bed with the back of a hoe to ensure good soil contact. You can cover the area with loose straw or grass clippings to help prevent the soil from drying out before the plants germinate.

• If no rain is forecast, water in well, and continue to water often during the germination period of your seeds to prevent the seed bed from drying out.

To turn the bed over to vegetable production:

• Dig in your crop before it goes to seed! Chop up large pieces with a shovel or even shears. mix into the soil.

3. Crop Rotation

Rotating groups of crops between beds can have some similar benefits to cover cropping for your garden soil. Planting legumes such as beans and peas can fix nitrogen for following crops. For more information on plant families and the multiple benefits of crop rotation, see the Selecting Crops for the School Garden how-to guide.

4. Liquid Soil “Teas.”

Compost tea is made by steeping compost in aerated water. Other liquid applications can be made by steeping green, un-composted plants in water. The resulting teas are used for either a foliar application (sprayed on the leaves) or applied to the soil.

Compost tea, like compost, contains nutrients, microorganisms, and compounds called humates. Humates help plants better use nutrients already in the soil among other benefits. Although compost tea has some benefits as a fertilizer, its major contribution is in adding microorganisms to the soil. These provide protection against diseases, especially root diseases; improve soil structure with associated benefits of aeration and water retention; and improve nutrient uptake.

Why go to the trouble of making compost tea rather than just adding compost? First, compost tea makes the benefits of compost go farther. When sprayed on the leaves, compost tea helps suppress foliar diseases, increases the amount of nutrients available to the plant, and speeds the breakdown of toxins.


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http://www.aginclassroom.org/For%20Educators/Gardening_Resources/How-To-Guides_For_School%20Gardening/Selecting%20Plants%20for%20the%20School%20Garden.htm

http://www.aginclassroom.org/For%20Educators/Gardening_Resources/How-To-Guides_For_School%20Gardening/Selecting%20Plants%20for%20the%20School%20Garden.htm

How to make compost tea:

You will need:

• 1 five gallon bucket

• 1 gallon of mature compost or vermicompost (worm castings)

• 1 aquarium pump

• 1 gang valve (to divide the air supply into several streams)

• 4 gallons of water

• 3 feet + of aquarium hose

• Un-sulfured molasses

1. Attach 3 separate pieces of hose, each 12" long to the gang valve.

2. Place the gang valve onto the bucket and make sure the hoses reach the bottom of the bucket.

3. Fill the bucket with the water, attach the pump to the gang valve and run for about an hour to evaporate any chlorine in the water. (Chlorine will kill the microorganisms)

4. Stir in the compost and the molasses

5. Continue to run the pump for two to three days, stirring occasionally

6. Tea should smell sweet and earthy at this point. If it smells bad, add to your compost pile instead, but do not add to your garden. Try again!

7. Strain the tea and use to water or spray your garden. Tea must be used immediately after aeration has stopped or the microorganisms will die.

See the “Healthy Soil Bed” design at the end of this guide for another example of a method for making tea in the garden.

4. Other Amendments for Soils:

Although compost is generally a good all-round bet, and enough to help soil in most school garden settings, other soil amendments and fertilizers may be used in acute situations.

Most commercial fertilizers have 3 numbers on the front label, separated by dashes. For example: 5-10-5. This is the fertilizer analysis or percentage by weight of 3 major nutrients plants need: nitrogen, phosphorus and potassium, in that order. These are abbreviated as N-P-K. So a 10 pound bag of fertilizer labeled 5-10-5, would contain 5% nitrogen, 10% phosphorus and 5% potassium. The remaining 80% could be comprised of other nutrients and filler.


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Some amendments beyond compost include:

• Aged, composted manure can be used (do not use fresh manure) and its nutrient levels, as with compost can vary greatly, but is readily available and easily accessed by plants.

• Lime can help make your soil more alkaline and help with magnesium difficulties

• Alfalfa meal or pellets contain around 3 percent nitrogen, and are commonly used as an animal feed. They can be bought from farm supply shops.

• Fish emulsion (Ranges in content from 4:1:1 to 9:3:0); suitable for foliar feeding of seedlings and the spot treatment of transplants. It is reputed to prevent stress, stimulate root growth and provide cold protection.

• Greensand (Glauconite) A mined sandstone deposit (typically 0:0:3 or 0:0:6) used as a source of potassium. Also contains iron, magnesium, silica and other trace minerals. Is a common ingredient in potting mixes.

• Rock Phosphate can be used to add Potassium, Calcium and trace minerals. Typically 0:3:0.

• Soybean meal (8:0.7:2) Useful to augment N and P.

• Commercial Fertilizer such as a 5-10-10 combination.

To improve soil texture and drainage amendments include:

• Leaf mold: This is great for increasing moisture retention in soils. To make leaf mold, simply create a compost pile made up only of leaves. Cutting them up can speed the process. However expect it to take longer than compost, at least 6 months. This is a worth-while task if you have sandy soil.

• Peat moss to increase moisture retention

• “Turf face” to improve drainage.

• Compost! compost! compost!

5. Mulching

Mulching is another technique that we have given its own How-To Guide due to its highly valuable and wide ranging benefit in the garden. Mulching your soil prevents moisture loss in soil and can break down into extra organic matter. Using compost, leaves or leaf mold, straw, and other materials is a vital step in maintaining healthy soil. Sheet mulching can be used to build soil up and increase top soil. For more on this topic, see our Building the Garden Beds how-to guide. Also see this guide for information on double digging, a technique which improves soil texture and drainage.

6. Working With Contaminated Soils

When engaging in urban agriculture, which is accurate for many school gardens, lead and other contaminants are a real risk. If your soil test shows lead or other heavy metals, you will need to determine the level, and the next steps will be the main priority in your garden planning. Because of the possibility of small children eating or tasting soil, soils with lead levels exceeding 100 ppm should not be used for gardening at your school. In this situation, you would need to create a barrier between a container or raised bed and the ground, such as with pool


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http://www.aginclassroom.org/For%20Educators/Gardening_Resources/How-To-Guides_For_School%20Gardening/Building%20the%20Garden%20Beds.htm%23Lasagna

or septic fabric or a closed box. Excavating the soil and replacing it is also an option, but costly. There has been success absorbing lead with plants such as sunflowers and mustard greens, but this takes many years. These plants are then removed from the site and put into the trash. The Food Project in Boston conducted a study on this technique and determined that mustard greens could remove 300 ppm over the course of 7-10 years. This could be an interesting task for children to do in a new garden site for children in the future!

Even with levels under 100ppm, steps should be taken to minimize absorption of lead by plants:

Insert 7

Gardening Practices to Reduce Lead Exposure (Adapted from UMass Extension Center for Agriculture: Soil Lead: Testing, Interpretation, & Recommendations - see sources)

1. Locate your school garden away from the drip line of your school if it is an old building, and also away from heavily travelled roads.

2. Give planting preferences to fruiting crops (tomatoes, squashes, peas, beans, sunflowers, corn).

3. Add organic matter such as high quality compost to your soil to make up at least one-third of the soil in your beds. This will significantly reduce lead availability. Organic compounds bind lead and make it less available to plants.

4. Maintain soil PH levels above 6.5. Lead is relatively unavailable to plants when the soil PH is above this level. If needed, add lime. Lead is also less available when soil phosphorus levels are high.

5. Wash hands immediately after gardening and prior to eating. (Good practices in general for the school garden)

6. Discard outer leaves before eating leafy vegetables. Peel root crops. Wash all produce thoroughly.

7. Protect garden from airborne particulates using a fence or hedge (fine dust has the highest lead concentration).

8. Keep dust in the garden to a minimum by maintaining a well-mulched, vegetated, and/or moist soil surface.


15

healthy soil bed herbal tea bed

!ese plants will be able to be harvested in the spring near the end of the school year to make a natural liquid fertilizer. Pair with rainwater collected from your garden shed.

establishment

Plant dwarf comfrey one foot in from the edges of the bed. Plant yarrow 3 feet from outside edge and seed white clover in the spaces in between. Water in during establishment.

fertilizer recipe

For comfrey, if you are starting with a newly established plant, cut the leaves once in June to prevent "oweringand allow the plant to grow and die back so as to build up reserves. Once the plant is well established, cut itbefore "owering in May when about 2# high. Don’t cut later than September to allow the plant to recoverfood reserves before winter dormancy. As comfrey plants become strong they will be ready for cutting every4 or 5 weeks giving 3 to 5 cuts per season. For yarrow, cut part of the plant in early June with comfrey leave the rest to grow back. Leave white clover in the ground as a low growing nitrogen $xing groundcover.

Place the plant’s leaves into a large container, preferably one with a tap or hole at the bottom, and a tight lid atthe top to exclude water and "ies and keep any smell inside. Some recommend simply covering the bottom ofthe bucket/container with leaves while others advise to $ll the bucket full. A blackliquid smelling of ammonia will soon collect in the bottom. !e solution needs to be diluted 15 - 20 times with water before application in the garden (For comfrey, this results in an N.P.K. = 0.5 : 0.4 : 3.8. - high in K).

(adapted from Make your own liquid garden fertilizers by Mark Krawczyk)

Maintenance

Water and weed as needed. Plants can be le! or cut back for the winter.

!ese plants will be able to be harvested at the beginning of the shcool year to make herbal tea. Pair with a lesson on drying herbs to store tea through the winter.

establishment

In eight foot by 4 foot raised bed plant new jersey tea and anise hyssop one and a half feet in from the edges of the bed. Plant echinacea four feet from the edges the mint and lemon balm four feet in. Water in during establishment.

Maintenance

Water and weed as needed. Plants can be le! or cut back for the winter.

scale 1/2”= 1’scale 1/2”= 1’


16

Insert 8:

Bed design by Lisa DiPiano of Mobile Design Lab, Northampton MA

Sources

USDA Natural Resources Cons. Service

State Office 451 West Street

Amherst, MA 01002

(413) 253-4350

Web Site: www.nrcs.usda.gov

http://soils.usda.gov/sqi/assessment/assessment.html

http://soils.usda.gov/sqi/concepts/soil_biology/soil_food_web.html

Local USDA NRCS Offices:

Barnstable: (508) 771-6476

Greenfield: (413) 772-0384

Holden: (508) 829-4477

Northampton: (413) 586-1000

West Wareham: (508) 295_5151

Westford: (978) 692-1904

* Free list of educational materials.

National Assn. of Conservation Districts

P. O. Box 855

League City, Texas 77574-0855

(800) 825_5547 Fax (713) 332 5259

Web Site: www.nacd.net


Soil & Water Cons. Society of America

7515 Northwest Ankeny Road

Ankeny, IA 50021-9764

(800) THE Soil Fax: (515) 289-1227

Web Site: www.swcs.org



17

http://www.nrcs.usda.gov

http://www.nrcs.usda.gov





http://www.nacd.net

http://www.nacd.net

http://www.swcs.org

http://www.swcs.org

Other Soil Web Sites

Soil Society of America

www.soils.org

National Wildlife Federation

www.nwf.org

USDA Agricultural Research Service

Kids Science Projects

www.ars.usda.gov/is/kids/fair/story.htm

NASA Goddard Space Flight Center

Soil Activities for Kids

http://ltpwww.gsfc.nasa.gov/globe/index.htm

Project Soil

http://projectsoil.org/project_soil

Soils and Conservation Website

with Soil Zoo

www.waite.adelaide.edu.au/school/Soil/index.html

The University of Massachusetts Soil and Plant Tissue Testing Laboratory. (413) 545-2311 or e-mail to [email protected]. http://umass.edu/plsoils/soiltest/

The Illinois Agriculture in the Classroom Ag Mag Issue 22

The National Wildlife Federation’s Educators Guide and information supplied by Al Averill, Greenfield MA Office, USDA NRCS.

On Compost Tea:“Fine Gardening” website: http://www.finegardening.com/how-to/articles/brewing-compost-tea.aspx

Pensylvania Department of Environmental Protection website: http://www.dep.state.pa.us/dep/deputate/airwaste/wm/recycle/Tea/tea1.htm

Worcester Roots “Lead Safe Yard Manual” : http://www.worcesterroots.org/2011/08/15/lead-safe-yard-manual/

Soil Lead: Testing, Interpretation, & Recommendations: Prepared by Tracy Allen, Lab Supervisor, UMass Soil and Plant Tissue Testing Laboratory; John Spargo, Assistant Extension Professor of Soil and Nutrient Management and Director, UMass Soil and Plant Tissue Testing Laboratory; and Baoshan Xing, Professor of Soil Chemistry. January 2012.


18

http://www.soils.org

http://www.soils.org

http://www.nwf.org

http://www.nwf.org

http://www.ars.usda.gov/is/kids/fair/story.htm

http://www.ars.usda.gov/is/kids/fair/story.htm





http://www.waite.adelaide.edu.au/school/Soil/index.html

http://www.waite.adelaide.edu.au/school/Soil/index.html

mailto:[email protected]

mailto:[email protected]

http://umass.edu/plsoils/soiltest/

http://umass.edu/plsoils/soiltest/

http://www.finegardening.com/how-to/articles/brewing-compost-tea.aspx

http://www.finegardening.com/how-to/articles/brewing-compost-tea.aspx

http://www.dep.state.pa.us/dep/deputate/airwaste/wm/recycle/Tea/tea1.htm




http://www.worcesterroots.org/2011/08/15/lead-safe-yard-manual/

http://www.worcesterroots.org/2011/08/15/lead-safe-yard-manual/

The Food Project website, Boston MA

http://thefoodproject.org/soil-testing-and-remediation

Rodale's All-New Encyclopedia of Organic Gardening: The Indispensable Resource for Every Gardener. Rodale Books: 1993, Fern Marshall Bradley (Editor), Barbara W. Ellis (Editor)

Images

http://bugs.adrianthysse.com/wp-content/uploads/2012/01/centipede.jpg

http://www.biologycorner.com/worksheets/earthworm_observation_living_key.html

http://www.onewaypestcontrol.com/spring-tails

http://www.pestmall.com/blog/pest-info/other-pests/millipedes

http://insects.tamu.edu/fieldguide/aimg1.html

http://nesoil.com/properties/color/sld010.htm

P. O. Box 345 Seekonk, MA 02771www.aginclassroom.org

Please Visit the Massachusetts Agriculture in the Classroom Websiteto tell us how you used this Soils Resource for the School Garden.

Thanks!

Resources for Building the Garden Beds

Local and National Organizations

Massachusetts Department of Agricultural Resourceswww.mass.gov/agr

Massachusetts Flower Growers Association

Massachusetts Nursery & Landscape Associationwww.mnla.com

National Gardening Associationwww.garden.org &www.kidsgardening.org

UMass Extensionwww.umassextension.org/index.php/information/gardening

UMass SoilTestingwww.umass.edu/soiltest/

USDA Food and Nutrition Program

USDA Plant Hardiness Zone MAPwww.usna.usda.gov/Hardzone/ushzmap.html

US Botanic Garden - Planning & Plantingwww.schoolgardenwizard.org

Other Curriculum & Resources Websites

American Community Garden Associationwww.communitygarden.org/docs/how-to_manual.pdf

American Horticulture Societywww.ahs.org

California Agriculture FoundationGardens Curriculumwww.cfaitc.org/gardensforlearning

Gro Edibles

Junior Master Gardener Programhttp://jmgkids.us

My Healthy Schoolwww.myhealthyschool.com/gardens/starting.php

New York City’s School Garden Programhttp://growtolearn.org

Project Life Lab Science & School Gardenswww.lifelab.org

School Garden Weeklyhttp://schoolgardenweekly.com

Soil & Water Conservation Societywww.swcs.org

School Garden Transformationswww.schoolgrounds.ca/projects.html

USDA Natural Resource Conservation Servicewww.nrcs.usda.govhttp://soils.usda.gov/

Vegetable Garden Basics - Rutgers

Raised Bed Container image - http://images.taunton.com/enewsletters/vg/kg08-raised-beds-09.jpg

Information for this How-To-Guide for Getting Started in the School Garden

Thank you to the Massachusetts Department of Agricultural

Resources for a Specialty Crops Grant that supported development of


19



http://www.amazon.com/Fern-Marshall-Bradley/e/B001ILOBP0/ref=ntt_athr_dp_pel_1/177-2063210-3581700

http://www.amazon.com/Fern-Marshall-Bradley/e/B001ILOBP0/ref=ntt_athr_dp_pel_1/177-2063210-3581700

http://www.amazon.com/Barbara-W.-Ellis/e/B001HD13JG/ref=ntt_athr_dp_pel_2/177-2063210-3581700

http://www.amazon.com/Barbara-W.-Ellis/e/B001HD13JG/ref=ntt_athr_dp_pel_2/177-2063210-3581700













http://www.aginclassroom.org/

http://www.aginclassroom.org/

Education

Soil in the Massachusetts School Garden