Soil Health and Fertility 

Good soil drains well but retains plenty of moisture that roots can access. It is easy to dig and full of organisms, such as earthworms, beetles, bacteria and fungi. Organic matter is a vital component of soil and is broken down by tiny organisms to release nutrients and improve the soil's water-holding capacity. Healthy, fertile soil is a rich dark brown, but whatever the color of yours, improve it by digging in organic matter, such as compost and manure, or applying it every year as a surface mulch over well-watered, moist soil.

Knowing Your Soil's pH 

The pH scale measures the degree of soil acidity, which determines the availability of nutrients, as well as the presence of beneficial soil organisms and less desirable soil-borne diseases. Low numbers on the pH scale indicate acidic soil; pH 7 is neutral; higher numbers show an alkaline soil. Garden soils normally fall between pH 4.5 and pH 7.5, but the ideal for vegetables is pH 6.5. Lime can be applied to increase the pH, but it is more difficult to lower it. Soil testing kits are widely available and easy to use. Simply mix a soil sample in a test tube as directed, and compare the color of the solution to the chart to determine the pH.