Get Down and Dirty--Spring Is Coming

While the ground is still moist, and the days cool, you might want to consider doing what is probably the hardest and unquestionably the most important job in the garden: improving the soil.

If things do not grow as well as you might wish, there are three likely causes: too much or too little water (a tough one to diagnose), too much shade (very common) or a soil that is too heavy, too sandy or too rocky. A poor soil is the easiest to correct.

If you go outside and take a look, you will find all sorts of telltale clues. Are dirt clods lying about? Are there cracks? When you water, does the water run off and refuse to soak in? Are there puddles after a rain? These are signs of a heavy clay soil.

Or, when you water, does the water disappear as fast as you apply it? Does the soil surface look dusty or gritty? Does a lot of the soil end up in the house, coming in on shoes and cats’ feet? These are signs of a sandy soil. (A rocky soil is simply full of rocks, though between the stones may be a clay or sandy soil.)

It is important to note that there are many plants perfectly suited to either of these soils, and you should go out of your way to choose trees and shrubs that don’t need a modified soil but will thrive in just what you have. Plants that require “fast drainage,” such as those from Mediterranean climates or our own natives, are prefectly suited to “well-drained” soils--soils that let water run in and right on through, with no puddling.

Many of the most ordinary and carefree plants do just fine in a clay soil--if not over-watered--because clay soils hold onto moisture and tend to be rich in plant nutrients. In a clay soil, trees and shrubs will need regular watering when young, but then they will need very little because clay soils are reservoirs. You must be very careful not to over-water trees and shrubs in a clay soil, especially in summer. Once a month is about maximum.

There also are flowers and vegetables that will grow just fine in these soils, but most want something much better, perhaps because they are short-lived or because they are such heavy producers. Whatever the reason, these belong in their own beds of richly prepared soil, and now is the time to prepare such beds--for annual and perennials flowers, bulbs and vegetables.

The way to make a sandy or clay soil a better home for these plants is the same: Add organic amendments to the soil. Organic amendments are things like specially prepared shavings (they have nitrogen added and are called nitrolized shavings). They are sold by the truckload or by the bag, the more expensive way to go.

You can find some fancy formulas for preparing a soil, but, in general, to prepare a 100-square-foot area, add four 3-cubic-foot sacks of soil amendment (a common size), or about half a cubic yard (truckloads are measured in cubic yards). If you buy a truckload, ask for an organic soil amendment.

If buying by the bag, ask your nursery person for the same thing, but it will have a trade name, such as Soil Builder or Amend. You do not want to buy topsoil (though that is the yellow pages listing under which you look for soil amendments) or potting soil.

If you are a little weak in math (as I am), 100 square feet measures 4 by 25 feet, 10 by 10 feet, 6 by 16 1/2 feet and so on. Whatever the area you are planning to improve, simply separate it into 100-square-feet sections so you can better keep track of things--things like fertilizer, which you also must add, at the rate of 2 pounds per 100 square feet (a 1-pound coffee can holds about 2 pounds of a granular fertilizer, a complete all-purpose kind with numbers like 10-12-12 or 8-8-8 on the label).

To add these materials to the soil, you first must dig up the soil in a rough fashion. This is the reason to do this work now, because you don’t want to do it on a hot day, and you don’t want to work in a dry or wet soil. The soil should be somewhere in between, as it is now near the end of the rainy season. Too dry and it will be as hard as concrete if it is clay, or too dusty and hard to wet again if it is sandy. If clay is too wet, it becomes like glue sticking to the spade and fighting you every inch of the way.

Use a spade and dig as deeply as you can, turning each spadeful on its side. Now spread the organic amendments and fertilizer on top. You will end up with about a 4-inch layer. Now mix soil and amendment together, using a spade or spading fork--or better yet, a tiller (you can rent them). Mix until they are thoroughly blended.

The fluffy soil that results should be recompacted by walking on it, and then it is ready to plant. Everything you do in the soil from now on, from planting to watering to weeding, will be incredibly easier, and the plants so much healthier. It’s the prefect way to get ready for spring.