Getting Soil in Top Shape Helps Seeds See Daylight

Good gardens start from the ground up. Before a single seed is dropped into the ground, pull back any winter mulch, fertilize, adjust the soil acidity and till.

Although mulches such as leaves and straw protect and enrich the soil, they also insulate it, keeping it cold in spring.

In cold soil, seeds rot rather than germinate, and roots of transplants shiver rather than grow. Pull any mulch aside to expose the soil to the warm sun. Cart the mulch to your compost pile or set it aside to put back on the soil once the weather turns hot.

Fertilizer is needed to replace nutrients harvested as vegetables and fruits or otherwise lost from the soil since fall. How much? Ideally, a soil test supplies this information. As a guideline, sprinkle about 3 pounds of a fertilizer containing 5% nitrogen (such as 5-10-5) per 100 square feet.

This one fertilizer will supply nitrogen, phosphorus and potassium, the three elements needed in greatest quantities by plants. (Their respective percentages are indicated by the three numbers on the label. Adjust the rate accordingly for fertilizers containing more or less than 5% nitrogen.)

If you are an organic gardener and want to avoid synthetic fertilizers, fortify your soil with nitrogen from soybean meal or cottonseed meal, at 3 pounds per 100 square feet. Wood ashes, applied at a half-pound per 100 square feet, supply potassium. Compost or manure also provide nutrients.

Limestone reverses the trend of many soils in the East to become increasingly acidic over time; in the West, soils often are not acidic enough and need sulfur to increase acidity. Once again, a soil test will tell you how much, if any, limestone or sulfur to apply.

The final phase of spring soil preparation is tillage, a practice that uproots weeds and smooths and aerates the soil.

Two rules for tillage are: not too much and not too soon.

Not too much--The objective in tilling a garden is not to reduce the soil to fine powder. A range in particle sizes leaves a good balance of pore sizes for the air and water needed by plant roots. Control the urge to repeatedly run your power tiller up and down the rows. Nothing beats tillage with a shovel and a rake for tempering the tendency to overwork the soil.

Not too soon--Wait for the soil to dry somewhat before tilling. Working a wet soil, especially one rich in clay, which is so common in much of Orange County, ruins the soil structure, making the soil good for sculpture but poor for plant growth. Squeeze a handful of soil. It should crumble easily. If it wads up, let the soil dry more before tilling; if it feels rock hard, a little moisture is needed to soften it.

Not only should you avoid tilling your soil when it is wet, but you should also avoid walking, bicycling or driving on it. Instead of “Keep off the grass,” remember “Keep off the dirt.”