Delicious Dirt -

Got Dirt?

When you look out at the garden (from the top), your first answer may be "YES, of course, I do!"

But, how deep is your garden soil?

One of the urban farming dilemmas is the fact that once a builder digs a foundation for a house, many times, the ground gets covered with clay from the hole that was dug. Then, to sell the house, a shallow layer of topsoil is added, enough to get grass to grow, but not much more.

So, to find the true answer to this question, dig 4 or 5 holes in the area where to plan to place your vegetable patch. You are going to need at least 12 to 16 inches of good soil, in which to grow your your vegetables.

Don't fret if your short on garden soil, as your local Clover's Garden Center, has plenty of garden soil and ammendments available for you.

Raised Beds

If you discover you have next to no topsoil, and do not want to struggle with removing the clay, or rocks you discover lurking under the surface - consider building a raised bed garden. Now, you can fill the planter with the best soil possible, to encourage your gardening success. If done correctly, you can sit pleasantly along the edges to do weeding, and harvest the fruits of your labor. They are also an excellent choice if you have any accessibility issues, as rather than bending down to the garden, you can bring the garden up to you!

pH - acid or alkaline?

Most garden vegetable crops prefer a soil pH around 6.0 - 6.5. This is slightly acidic.

Blueberries, eggplant, endive, raspberries, rhubarb, spinach, and watermelon prefer very acid soil (5.0-5.8 pH).

Cabbage, celery, cucumber, and thyme, are at the other extreme, prefering soil that is very alkaline (7.0-8.0 pH).

You can purchase a simple, easy to use, pH test kit at most hardware stores.

Recipe for Dirt

What is the ideal garden soil?

50% solids (organic & inorganic)

50% porous space
(room for air, water, & plant roots)

Inorganic matter is the fine rock particles. They come in 3 varieties: clay - finest sized particles, silt - medium sized particles, and sand - coarsest sized particles.

The ideal inorganic (texture) portion of garden soil is loam, which is:

20% clay
40% silt
40% sand.

Organic matter is decaying plant material.

This is the critical part for tasty soil (in a plant's opinion). Vegetable garden soil should be close to 1/3 organic matter - the decaying plant material and compost.

The best time of year to turn over your garden soil is late fall. You may turn it over again, lightly, in the spring, being careful not to compact it, with too much foot traffic. Also, spring is the best time to ammend the soil as needed.

So what does your soil need? Please keep reading...

Testing, 1, 2, 3, ...
(the simple jar test)

Gather the following items:

• 1 clean quart jar with a tight fitting lid
• clean water
• soil sample - take 5 hand trowel scoops of soil from about 4 inches deep in the garden - one each, from the 4 corners of the bed and one from in the center & mix together

Fill the jar with 2/3 water and 1/3 soil sample, leaving about an inch of air space at the top of the jar. Screw on the lid, and shake the jar vigorously for about a minute or two - until the soil is suspended in the water.

Allow the suspended soil to settle for about a minute, and place a mark on the side of the jar at the top of the layer that has settled out. This is the sand layer. It is comprised primarily of sand and larger particles. Set the jar aside, being careful not to mix the sand layer that has already settled and wait approximately an hour. Now, place a mark on the side of the jar at the top of the next layer to settle out. This is the silt layer. Again, place the jar aside for a full day, being careful not to shake or mix the layers that have settled out. After 24 hours, or when the water is once again clear (more or less), place a mark on the side of the jar at the top of the final layer. This is the clay layer. The percentage of each layer tells you what kind of soil you have.

See where your soil lies in the soil pyramid...

This simple test, can help you to better understand your garden soil. If you want more accurate results consider sending a soil sample to a soil testing service.

N :: P :: K (fertilizer)

N is for nitrogen. Simply put, nitrogen "greens up" vegetable plants.

P is for phosphorus. Phosphorus makes the roots strong and encourages flowering.

K is for potassium. Potassium is key in the plant's photosynthesis process, helping plants to metabolize their food to get energy. It helps the plant to function, like a plant.

They're all critical to healthy plants.

If you haven't had your soil tested for these nutrients, consider a 10-10-10 fertilizer when planting your garden in the spring.

One last note - compost and organic matter can go a long way, with helping to add nutrients to your soil.

Worms & Dirt

There may be no harder worker in the garden than the earthworm. Earthworms are voracious consumers of organic materials and leave a nutrient rich manure, called castings, along their trails as they nibble their way through the soil. These castings are neutral in pH, thus, healthy earthworm populations can help to eliminate problems with either high or low pH in the garden. In addition to producing up to half of their body weight in nutrient rich castings every day, earthworms also improve garden soil by creating channels which help to aerate the soil and improve drainage, and their slimy, nitrogen-rich secretions help to bind soil particles and increase soil moisture retention. A garden full of earthworms is likely to be nutrient rich, highly workable, and grounds for a successful garden.

(Speaking of grounds, please add your used coffee grounds and tea leaves to the garden - worms love them!)

For earthworms to prosper in your garden, they need a large supply of organic matter, adequate moisture, and oxygen. Additions of compost, thick mulches of shredded leaves, grass clippings, and other organic materials will encourage worm activity by providing food and habitat.

What about vermicomposting?

Learn more...

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