When Dishing Dirt Is a Virtue

The part of gardening that might be the least glamorous - gettingthe soil ready - happens to be the most important.

A short course of just what soil is, in broad terms, is theplace to begin. First of all, references to soil for the purpose ofgardening mean the top eight to 12 inches of dirt. Below that it iscalled subsoil and can be quite different from the layers above.

If you always wondered why experts keep urging "add organicmatter" to the soil - what is soil if it's not organic? - the realstory might come as a bit of a revelation. Ideal soil is 50 percentwater and air.

Only half of it is something you can actually hold in yourhands. That half in a …