Improving Soil with Compost

Using Compost to Improve a Soil

Adding compost to a soil does two things; it changes the physical structure of the soil and adds plant nutrients to it as well. The question becomes, “Does your soil need it?” Sometimes it does, sometimes it doesn’t. Learn to know if your soil needs compost or not before buying it.

This 2 inch layer of Viragrow compost will be dug into this soil about 6 to 8 inches deep. The soil will then be shaped into raised beds. It will last for about two years until more is added. Depending on the crop grown, fertilizer may or may not be needed for several months to a year.

Improving Soil Structure

Compost changes the physical structure of the soil. This can be a good thing when its needed or it can be unnecessary if its not. By adding compost to a soil it improves water drainage in soils that don’t drain water easily.

Soil drainage and aeration is improved because of the improved soil structure created by compost.

But, like a sponge it also holds water in a soil before it drains making it available for the plant to use. Mixing the right amount of compost into a soil can be tricky. You want the soil to drain water, but you also want it to hold water for plant roots.

At some point, when you find that balance between draining water and holding water, adding more compost to it is throwing your money down the drain…literally! Find the amount of compost to add and then stop! Add enough compost every year to maintain the ideal balance for the plants you are growing.

Plant Roots Must Breathe

Plant roots must “breathe” or they will suffocate and die. Adding more compost to a soil increases its “aeration” or the admission of “good” air full of oxygen into the soil and the releases of “bad” air from the soil. Some plants need more compost, or aeration, in the soil surrounding their roots than others. For instance, lawns and palms tolerate lower amounts of aeration in the soil while roses, flowering bedding plants, most vegetables and many ornamental trees and shrubs need more aeration.

Plugs or cores taken from a lawn improve drainage and root aeration which causes roots to grow deeper. This is mechanically doing what compost does naturally!

The amount of compost to add depends on which plants you are growing. But ALL plants tolerate aerated soils. Know the plants you are growing and add compost to soils when its needed.

Using Compost as a Fertilizer

Compost improves a soils structure for better drainage and it can add nutrients as well. The question becomes, “How much to add?’ The answer may surprise you. It depends.

A circle of rich compost such as Viragrow's can feed plants by releasing its plant nutrients. The compost remains in place to slowly improve the soil surface where feeder plant roots like to grow.

Some composts are “rich” in plant nutrients while others are not. Remember the old saying, “Garbage in, garbage out.” This is very true of compost. Compost can be very rich in plant nutrients when made from animal manures. Sometimes it can be so rich in nutrients that it must be applied carefully to avoid plant damage. Compost made only from plants is usually less “rich”. But both types of compost improve the soil physical structure which is enough to improve plant growth. Compost made from animal manure may have enough plant nutrients to stimulate plant growth for months! Plant leaf color and growth will tell you when plant nutrients are needed again.