Soil & Testing
the most abundant ecosystem on earth
The true life of the plant is the soil in which the seed or plant is birthed within.
- Soil is a living breathing entity and deserves respect.
- Within soil there exists millions and millions of living organisms, soil fungi, algae, bacteria, worms insects, water, carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, iron, boron, manganese, copper, zinc, molybdenum, chlorine and a whole host of other lives and chemical elements all designed to bring about the community goodness of the earth.
- One acre of soil may contain 900 lbs. of
earthworms, 2400 lbs. of fungi, 1500 lbs. of bacteria, 133 lbs. of
protozoa, 890 lbs. of arthropods and algae.
- Soil is a place where a seed finds it true home and thrives and grows to maturity and many times springs eternal.
- You must nurture and feed your soil and its inhabitants before you can feed anyone else.
- The presence of WORMS is a good indication that you have good soil.
- Water along with organic material is the formation of soil fertility.
- It takes 800-1000 years for 2.5cm thick layer of fertile soil to form in nature.
- A good soil can contain an approximately one million unknown species of microbes per gram.
- Every year add a new layer of soil to your already existing garden.
- Soil biology is designed as a carbon sink, about 57% of the biotics of soil is carbon.
Soil = 10"
three layers (horizons) of soil: topsoil, subsoil, parent soil
- For growing most vegetables a depth of 10-15 inches of top soil is needed, depending on what you are growing. You can get away with 8 inches when it comes to lettuces and salad vegetation, but that is not the best depth to operate from so go ahead and break soil for 10 inches to start with.
- Top soil can range in depth from 2" to 6 feet.
- you naturally improve your topsoil by adding organic matter on a regular basis.
there are five main soil types: (clay, sand, silt, chalk and peat)
the 3 types of basic soils are: Sandy, Clay, Silt
- a light soil of mostly larger particles which is well aerated and drains fast of water and fertilizer.
- They are easy to warm in the spring and easy to dig up.
- Acidic soils like sand for drainage and vegetables that grow beneath the ground need sand to expand in.
- Sand particles that are 0.05 -2.0 millimeters(mm) in diameter.
- a heavy soil of mostly fine particles.
- This soil easily attracts fertilizers and therefore holds nutrients tighter than sand.
- Water dries out more slowly and once the clay is dry, water has a hard time entering.
- Clay warms up slowly in spring and is hard to dig. And you do not want to dig clay when it is wet it just clumps.
- Clay particles are less than 0.002 mm in diameter.
- a soil that holds water and nutrients nearly as well as clay but drains much more readily.
- It is an unstable soil that has particles that are 0.002-0.05 mm in diameter.
Loam (Peat) soils:
- This is the ideal soil for growing a garden.
- It consist of intermediate size particles and is a loamy soil (mixture of soils) of approximately 40% sand, 40% silt and 20% clay.
- From here you have sandy loam, loamy sand, clay loam, sandy clay, etc.
Most soils fall within pH5.0-pH8.0.
- The best way to test soil is with your hand.
- The perfect soil is slightly moist and fluffy (friable), when you test it and it looks like a crumbled mess of slightly damp meal in your hand.
- It moves beautifully and does not fall out of your hand or clump up in it.
- If it is too clay it will stick together when wet or crumble like a cookie when dry, if it is too sandy it will separate too much if it is wet and pour out of your hand if it is dry.
You basically need a horizon (layer) of about
- 2 inches of clay in the subsoil (this is your natural bedrock earth layer),
- then the top soil of 6-12 inches should have about 1/3 sand, 1/3 compost and 1/3 growing soil.
- The percentages will vary depending on what you are growing and the pH level needed, and with that the sand and manure and other elements will increase or decrease.
- See Tomato Square Footage for detailed measures for soil and additives (click on the growing tomatoes page, then scroll down to Tomato Square Footage)
There are 4 different types of soil test you can make.
I conduct my own soil test, you can take a sample of soil and send it to your local cooperative extension office and they will do a thorough test for you. I buy Rapitest Soil Test Kit and this does the trick for me.
- Nitrogen (N) grows your stems and leaves and keeps them green.
- Low (N) can mean yellow leaves and low growth.
- High (N) can create lush foliage but delayed flowers.
- Phosphorus (P) is a major constituent of plant genetics and seed development.
- Low (P) stunts the plant growth and causes seed sterility.
- (P) aids plant maturity, seed yield, and fruit development.
- (P) increases vitamen content and aids the plant's resistance to disease and winterkill.
- Potassium (K) (potash) strengthens the plants.
- (K) helps in water uptake, to form carbohydrates and promotes protein synthesis.
- (K) Improves the flowering,color and flavor of fruit, it aids early growth, stem strength and cold hardiness.
- Low (K) plant is stunted and has a poorly developed root system, spotty leaves, curled and dried on the edges.
The nice thing about adding organic matter to any soil is that the organic matter will bind to any pollutants in your soil and keep them out of your plant roots.
Farms in developing countries that use organic techniques produce an average of 79% more than farms that don't. (Rodale Institute)
The Garden Primer - Barbara Damrosch
Rodales's Ultimate Encyclopedia of ORGANIC GARDENING - Rodale Press
Compost Gardening - Barbara Pleasant & Deborah L. Martin
Growing Vegetables & Herbs - Mitchell Beazley
GOLDEN GATE GARDENING the complete guide to year-round food gardening in the San Francisco Bay Area and Coastal California - Pam Peirce
The Organic Gardener's HANDBOOK OF NATURAL INSECT AND DISEASE CONTROL - Ellis and Bradley
Organic GARDENING - Geoff Hamilton