Vegetable Gardening 101: Soil

Soil Sketch

There are a few essentials when it comes to growing vegetables, or any plants for that matter. Soil has many jobs in the life of a plant, holding nutrients, retaining just the right amount of water and supporting the plants by stabilizing the roots to name a few.

Soil is alive with all sorts of organisms. The four main organisms found is soil are as follows:
The Soil Crust- These guys live on the top the soil and are formed by living organisms and their by-products, creating a crust of soil particles bound together by organic materials. There are two types of crust, biological (what I just explained) and chemical/physical. Chemical/Physical which is an inorganic crust such as a salt crust or platy crust usually formed by trampling.
Nematodes- Earth worms! These are great little guys chow down on bacteria, fungi, and plants. Their “by-product” making excellent fertilizer. Their worm holes help to keep the soil from getting too compacted. They multiply when carbon is added to the soil, this happens from adding mulch, compost or growing a cover crop.
Bacteria- The presence of good bacteria keeps pests down, prevents plant disease and breaks down both living and non living matter into nutrients for growing plants. The benefits of good bacteria are endless.
Mycorrhiza- These are a fungi type organism who’s job is to help plants extract nutrients from the soil. They do this by growing into composting plants and animal stuff and convey their nutrients back to the plants roots.

Different types of soil are classified by the size of the particles that make them up. The goal type is “Loam” . Loam is neither too sandy or too clayey. This soil drains well but retains just the right amount of moisture. This type of soil can be achieved no matter where you live, it just takes time and lots of organic matter. Adding organic matter, every year between crops will improve your soil and in a few years you will have wonderful healthy soil. This is very important because soil feeds your plants and the plants feed you. Growing vegetables in nutrient void soil will result in nutrient void vegetables. You can purchase soil tests that will tell you if you soil is low on any of the main plant growing nutrients Phosphorus (P), Nitrogen (N) and Potassium (K) as well as the pH.

pH refers to the acidity and alkalinity of your soil. A good pH contributes greatly to a good harvest. If you don’t want to buy a pH test you can test your soil by taking 2 empty mason jars, fill each half way with soil and fill to the top with water. Shake to get everything well mixed. To one jar add a few tablespoons of baking soda, if this fizzes your soil is more acidic. To the other jar add a few tablespoons of distilled vinegar, if this fizzes your soil is more alkaline. If neither fizzes your soil is pretty well balanced. Adding some wood ash to your acidic soil will help to balance it.

Chemical fertilizer is usually a combination of P, K, N. It is water soluble, thus making a quick snack for plants. However, using chemical fertilizer over time will cause more harm than good. They tend to kill most soil organisms that produce plant nutrients naturally. Even though they are getting the three basic nutrients plants and humans need many different micro nutrients that are not available in a chemically fertilized soil. The chemical fertilizer, being water soluble washes away quickly and adds to ground water pollution as well.

Nitrogen is used by plants to build healthy stems and leaves. Plants lacking nitrogen will grow very slowly and be rather yellow-ish in color. Nitrogen is usually the first nutrient to leave the soil especially when crops like broccoli, cabbage and other brassicas as well as corn, are planted.

Phosphorus is needed for plants to grow a healthy root system and flower. This nutrient stays with the soil much longer than nitrogen and can be found in wood ashes as well as other sources.

Potassium is used by plants to resist disease, develop chlorophyll which allows them to convert sunshine to food, and strengthen their tissue. This too can be found in wood ashes as well as other sources.

Some plants use more of some nutrients and less of others by adding good organic matter and rotating your crops will ensure your soil to maintain it’s health and in time improve. Legumes could be considered  a bonus crop because most vaierties put more nutrition into the soil than they take out.

Weeds are another way of telling what’s going on with your soil. The weeds that show up in your garden can indicate the pH of your soil, how well your soil drains, if you have sandy or heavy soil, hard crusted or chemical/physical crust. Different weed prefer different soils.

So far we’ve talked a lot about soil types and soil nutrition, but lets say you live downtown and the closest thing to soil you see is what is in the pots of your house plants. Potting soil is a mixture of peat, humus and organic matter, in quantities that allow for good plant nutrition and drainage. Why people throw out their potting soil at the end of the season is beyond me! Adding some compost, compost tea or organic fertilizer is all it could be lacking. Plants with adequate water and nutrition will very rarely need repotting or get root bound. Plants send out roots for water and nutrients if what they need is readily available there is no need to go any farther.

A good rule of  thumb is healthy soil looks a lot like chocolate cake crumbs. Soil that is growing healthy looking plants (even if it just grass) is probably pretty healthy soil and with a little organic matter can produce some amazing vegetables.

I could go on forever about soil, but if I haven’t lost you already I would soon. This was just a brief overview of a very large subject. If you have specific questions I would be happy to do my best to answer them.

Next topic : Vegetable Gardening 101: Compost and Organic Material
Previous topic: Vegetable Gardening 101: Introduction

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  1. Great article. I was just reading a post about how tomatoes need a good amount of calcium in their soil. It’s a great preventive step to keep them from getting brown. The article said that composted eggshells are full of calcium so they are great for tomato beds.

    1. I’m a crazy egg shell saver! I used to keep them in a pale in the freezer. Right next to the old coffee grounds. Both went to the garden in the spring. Now it all goes to the same compost pile.

      Thank you for sharing!