Gardening Tips - Garden Soil

The warming earth in spring brings gardens and gardeners to life. Bulbs thrust through the last layer of winter, announcing the arrival of another season of growth...while gardeners arm themselves with shovels, wheelbarrows, and bags of soil amendments, ready to mix those magic potions that will ensure their gardens' vigorous growth and abundance.

Garden soil is made up of four basic parts: minerals, organic matter, water, and air. The parts are not equal, and while organic matter is essential to the plant's ability to utilize water, air, minerals, and other nutrients, it often makes up less than 1% of the total. Soils that are sandy or basically clay need rich, ition of potassium, a nutrient essential for cell division, but they may be low in phosphorus, an element necessary for root growth and flowering or fruiting. While soil may already have the nutrients necessary for plant growth, a high pH (more than 7.5) or low pH (less than 6.5) may prevent plants from absorbing these nutrients. Add lime or oyster shells to raise the pH of acidic soils and garden sulfur to lower the pH of alkaline soils, which need fresh organic material in greater quantities than acidic soils. You can get a kit to test the pH level of your soil, or you can have it tested professionally by a private laboratory, the state Cooperative Extension Service, or the county extension agent.

Simple Soil Test

Although the experienced gardener can grab a handful of soil and crumble it to determine its texture, the novice may want to perform this simple water-jar test to determine the sand, silt, and clay content of the soil.

1. Add a cupful of soil and a teaspoon of non-sudsing dishwasher detergent to a one-quart jar. Fill the jar half full of water, close it tightly, then shake vigorously for a minute or two.
2. Place the jar on a level surface, and after 1 minute, mark the level of the settled soil. This is the sand layer.
3. After 2 hours, mark the next level, the silt layer.
4. After 2 days, mark the final, clay, level.
5. Compare the depth of each layer to the total depth of the soil to determine the percentages of each.

Soil that is about 40% sand, 40% silt, and 20% clay is called loam, and it provides an ideal growing environment for a wide variety of plants. Soils that are high in sand or clay will need to be amended with organic matter, such as compost, to make them more hospitable to plants.