Soil condition is of the essence when it comes to growing vegetables – or any plant for that matter. Many garden experts suggest that you focus on maintaining the health of your soil even as you nurture your plants (and there’s lots of scientific data supporting their position).
It’s healthy soil that helps your vegetable garden thrive and prosper.
Photo Credit: ©2002 Dolezal Publishing/Image Point
Healthy soil is composed of many organic, mineral and even living elements – microbes that digest and break down decaying plant matter into its components, making the food that vegetable plants need to thrive and prosper.
The three most common nutrients found in garden soil are nitrogen (n), phosphorus (p) and potassium (k). Nitrogen is the only one of the three that’s water-soluble, and it’s the one necessary for foliage growth. Too little nitrogen stunts growth, while too much causes lush foliage at the expense of flowers, fruit and seed.
Phosphorus, a common element found in natural abundance in many soils, affects plant vitality and aids flower, fruit and seed formation. Too much phosphorus limits a plant’s uptake of copper, iron and zinc, stunting its growth.
Potassium influences the growth of both stems and roots by influencing efficient protein and carbohydrate synthesis inside plant cells.
Your soil needs all three nutrients for your plants – and garden – to thrive. The amounts of these nutrients found in your soil depend on the minerals contained in the bedrock underlying your site.
Macronutrients – as nitrogen, phosphorus and potassium are known – are just part of the story. More than 30 micronutrients and dozens of trace elements are found in most soils as well. Their presence or absence depends mostly on two factors: the quantity of decomposed organic material that the soil contains and the maintenance of a proper acid-alkaline balance to break the ionic bonds of these compounds and free them for use by your plants.
The best vegetable garden soil is loose, fertile loam with equal parts mineral clay, silt and sand, mixed with ample decomposed organic material. (Such soil drains easily and retains ample air while it avoids compacting.) It has an acid-alkaline balance measuring 6.0-6.8 on the pH scale, a reading that’s slightly acidic.
How do you know what kind of soil you have? By testing it for texture, nutrients and pH. Many nurseries and garden centers provide testing services to assess soil and recommend necessary amendments, as well as offer reliable do-it-yourself test kits. If you enlist the services of your local Cooperative Extension or a laboratory to analyze your soil, follow its staff’s instructions on how to properly collect and submit a soil sample.
To perform a soil test at home, follow these easy steps shown in the photographs and described in their captions.
Soil Test - Step 1
Dig a hole at the planting site. Using a clean container, collect a small amount of soil from along the hole’s side, 3-4 inches below the surface. (For large gardens, thoroughly mix soil from different locations or evaluate each area separately.)
Photo Credit: ©2002 Dolezal Publishing/John M. Rickard
Soil Test - Step 2
Using part of the moist soil sample, squeeze the soil in your fist, then open your hand. If the sample feels gritty and falls apart when poked with a finger, your soil contains excess sand. If it holds together, roll it between your forefinger and thumb to produce a cylinder-shaped soil rope. If it breaks before reaching a ½ inch long, your soil has ample silt or loam. If the rope of soil reaches 1 inch or more before breaking, your soil contains excess clay.
Photo Credit: ©2002 Dolezal Publishing/John M. Rickard
Soil Test - Step 3
Using a store-bought home soil test kit (and carefully following all package instructions), measure relative amounts of the three soil nutrients – nitrogen, phosphorus and potassium. Always use distilled water (available at most supermarkets and drug stores) when testing soil.
Photo Credit: ©2002 Dolezal Publishing/John M. Rickard
Soil Test - Step 4
Determine your soil’s acid-alkaline balance using a pH test kit. Again, use distilled water and carefully follow all test instructions for best results.
Photo Credit: ©2002 Dolezal Publishing/John M. Rickard
Soil Test - Step 5
Electronic meters check soil pH, too. If using an electronic meter, verify its accuracy by first testing cow’s milk, which has a pH of 6.5-7.0. Thoroughly clean the probe before testing your soil sample.
Photo Credit: ©2002 Dolezal Publishing/John M. Rickard
