YOU ARE HERE: LAT HomeCollections


Products Not All They're Marketed to Be

August 10, 1996|From Associated Press

"A growth miracle for your plants."

"An all-organic growth enhancer."

"Loosens and mellows the soil, promotes larger root systems, increases nutrient and water intake."

These are typical claims made for some esoteric new garden products. These products sometimes are called "biostimulants," a name that tells what these products do rather than what they are.

Biostimulants are not fertilizers meant to correct gross nutrient deficiencies but are mixtures of one or more such things as microorganisms, trace elements, enzymes, plant hormones and seaweed extracts.

Biostimulants are used in small amounts and, to paraphrase the manufacturers, mimic natural processes already occurring in plants or soils.

Alluring, isn't it, the prospect of 1 pint of liquid bringing the benefits of 7 tons of manure (a claim of one biostimulant manufacturer)?

Makes one want to trade in the compost fork and shovel for a set of measuring cups. But does the performance of biostimulants really match their claims? Are those dark liquids true elixirs, or are they modern snake-oil potions?

Though all the ingredients found in biostimulants are known to benefit plants and soils, these ingredients are not found only in plastic jars with labels; they also occur naturally in soils, especially fertile soils.

If you annually enrich your garden with barrow loads of compost, leaves, grass clippings and the like, your soil already is crawling with microorganisms and teeming with enzymes and hormones.

Before you are impressed by a product having a billion bacteria per gram, which will be dispersed when applied, realize that each teaspoon of a fertile soil already has a few million bacteria.

Despite the fact that the contents of a bottle of a biostimulant occur naturally in soils, manufacturers enthusiastically promote treating soils and plants with these products. Such promotions are not always based on rigorous experiments, though.

In some cases, supporting experiments are inapplicable or of negligible value when applied to the average backyard soil. For example, would you be willing to purchase, then go through the trouble of mixing and applying a product to increase your tomato yield by only 0.4 fruits per plant? (This statistic was gleaned from an actual research report).

This is not to say that these new products totally lack merit. Recently bulldozed building sites with compacted soils, a compost pile made solely of sawdust and soils that have been subjected to heavy pesticide use are examples of situations where some of these products might be useful.

But never substitute any of these products for correct fertilization, regular additions of organic matter to the soil and other good gardening practices.

Don't put the cart before the horse: Just because fertile soils are teeming with fungi and rich in enzymes does not mean that adding fungi or enzymes builds fertility.

The way to maintain high levels of soil microorganisms, trace elements, enzymes and other wholesome ingredients of biostimulants is by providing food for the microorganisms. These foods are bulky organic materials such as leaves, grass clippings, compost and manure.

Los Angeles Times Articles