Using Compost When Transplanting Plants
Perhaps one of the best times to use compost, especially if the supply is severely limited, is when transplanting small plants into or around the garden. However, do not use compost either alone or in conjunction with loose soil in the planting hole when planting trees and shrubs. Most gardening books printed before 1989 strongly recommend this, but more recent studies have found that a compost-rich soil mix around the roots of a newly planted tree or shrub, tends to encourage the roots to continue to grow in the planting hole rather than venturing out into the plain old soil surrounding that hole. The roots then grow in a circle and after a few years the plant gets literally strangles itself and dies. So use compost on trees and shrubs only as suggested above, not at planting time.
Compost in planting holes intended for flowers, vegetables and other small plants is not a problem, and, in fact, it gives these plants a wonderful start. The process is very simple. Every time you dig a hole for a new plant or a transplant, throw in a handful of compost just before setting the plant in the soil. The compost offers nutrients to help the plant withstand the shock of transplanting and then offers sustained nutritional support over the entire season. It also conditions and improves the texture of the soil in the immediate area of the plant.
Even annual flower transplants benefit from a dose of compost at planting time. Those homeowners who make it a routine practice to add some compost to the soil every time they plant, realize that after a few years they have improved the soil at planting sites all over the yard. Collectively that adds up to an extensive soil renovation over every part of the property where plants have been introduced. Those areas where annuals are planted every season have especially good soil after a few years.