Soil Gone Sour

THE REAL DIRT

March 14, 1993|By MIKE KLINGAMAN

Each year, before planting season, my garden and I get regular checkups. I visit my doctor, but the garden requires a house call.

These checkups are important. Both the garden and I need to be in top shape for spring. Me, for digging; the garden, for growing.

The latest tests produced mixed results. I passed my physical, after promising to shed 20 pounds.

However, the garden is ill. It suffers from acid indigestion, for which it needs a large dose of medication.

What the garden needs is a 500-pound Rolaid, or the same amount of powdered limestone. Either way, it's a prescription I doubt the pharmacy will deliver.

I know the garden has heartburn because I examined it with a soil-test meter, a battery-operated device which, when placed in the ground, measures the acidity of the soil.

The readings surprised me. Much of the garden soil is so acidic, you'd think it was living on Mexican food instead of organic fertilizers.

Adding lime will sweeten the soil and make it more palatable for my plants this summer. Liming the garden is like adding sugar to lemonade.

Most flowers and vegetables thrive in near-neutral conditions, which allow the plants' roots to absorb minerals from the soil. Those minerals won't dissolve in overly sour soil. Eventually the plants starve, no matter how rich the land.

Hence, the importance of soil tests. All garden loam looks the same to us, but plants can tell the difference. So check the acidity of your garden. Give the plants a break. Would you want to live in a world where everything tastes like lemon juice? Neither do plants.

On the other hand, certain plants like being sourpusses. My soil is perfect for raising azaleas, bleeding hearts and blueberries, all of which worship acid soil. But I want to grow beets, cabbages and cucumbers, which favor more alkaline conditions.

It's easy to sweeten the soil in small gardens or in pockets of a large yard. It's more challenging, and often futile, to try to change the chemistry of entire landscapes to accommodate one's favorite plants. Particularly in this age of acid rain.

As industrial pollutants fall to earth, nature suffers. Rainfall more sour than grapefruit juice has crippled spruce trees in the Appalachians, damaged half of Germany's 18 million forested acres, and triggered the demise of many species of Siberian lichens, the reindeer's main food source there.

Acid rain doesn't kill plants, it lowers their resistance to disease and hungry insects. Acid rain is the big reason I give my garden an annual checkup.

There are several ways to monitor the soil. Testing meters are small, neat and efficient: You plunge the probe into the ground, ++ as if taking its temperature, and read the needle on the gauge.

Commercial soil-test kits are also popular. Although they contain chemical solutions, these kits are inexpensive and easy to use. You needn't be a rocket scientist to follow the instructions.

Some gardeners prefer to let others analyze their soil. They send samples to professional soil-testing laboratories, or to the local cooperative extension service. The analysis takes several weeks complete.

Our ancestors had simpler methods of testing the acidity of the soil, without even breaking ground. Pioneers often chose their farmland by looking at the vegetation. Only a fool would clear a stand of pines for cropland, because pines thrive in acid soil.

Colonists also examined weeds for clues to the land's fertility. Plants such as chickweed, groundsel and lamb's-quarters usually mean the soil is rich and sweet, whereas daisies, dock and horsetail signal acid ground.

Of course, gardeners today can also resort to visual means to estimate soil acidity. For instance, yards filled with mosses or wild strawberries require a lot of lime.

On the other hand, cactus is a measure of alkaline soil. A yard full of cactus needs no lime at all.

But you might want to scatter some Band-Aids around.

Baltimore Sun Articles
|
|
|
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.