What is Planting Soil?
Most plants draw nutrients from the soil in which they grow. Hardier plants (such as desert and scrub plants) can thrive in nutrient-poor soil, but most require soil that is high in nitrogen with a reasonably balanced pH (on a 1-14 scale, a pH of 7.0 is neutral; anything less is acidic—the lower the pH, the more acidic it is—anything higher is alkaline). Adequate levels of phosphorus and potassium are equally important to proper development and the health of most plants, as are magnesium, calcium and sulfur, though to a lesser degree. Nutrient-poor soil can be enriched with fertilizers, but the best way to get a garden blooming is by using planting (or potting) soil.
Planting soils come charged with the aforementioned chemical nutrients in the form of compost and mulch, lending it a deep, dark, earthy appearance and odor. It can be costly, but there are ways of stretching its use.
Gardens made from hard-packed, nutrient-poor soil thrive best when the entire top layer of soil—as much as eight to ten inches—is stripped away and replaced with planting soil. Depending on the garden, this can cost hundreds or even thousands of dollars. A better solution is to dig a reasonably large hole wherever you want to plant a shrub or tree (a foot across and 10-12 inches deep for small shrubs, a foot across and two feet deep for large shrubs or two feet across and three feet deep for trees), fill it about a third of the way with planting soil, insert the plant’s roots, holding it upright in the center of the hole, and filling the rest of the hole with planting soil. Be sure not to bury the stock of the bush or tree and only the roots.
All plants—new and old—can benefit from planting soil. For older plants that are struggling, dig them up, taking care to cut as few roots as possible and replant them as described above. Be sure to remove as much of the old, useless soil from the roots as possible before replanting them; this also aerates the roots, which any plant would appreciate.
Different plants have different soil requirements. Always check with your neighborhood nursery before selecting a planting soil.
Planting soil is soil that has been specially prepared for planting. It contains the nutrients necessary for plants to thrive, and its pH balance has been adjusted to be suitable to the types of plants which will be grown in it. It is possible to purchase planting soil from garden supply stores, and also to prepare your own.
