How Does Your Garden Grow?

For many of us, spring means gardening -- and our pursuit of greener grass or pest-free flowers may lead us to fertilizers, pesticides and herbicides.

Recent studies, however, raise a red flag on chemical use, pointing to a possible link between herbicides and pesticides and diseases such as non-Hodgkin's lymphoma, other lymphoproliferative cancers, Parkinson’s Disease and other neurological problems such as memory loss. Experts are calling for more research, but the home gardener should play it safe.

"Make sure you read the directions," says George C. Hamilton, associate extension specialist for Rutgers University's Cooperative Extension Service in New Jersey. "We find that people don't read the labels completely, and that can cause problems."

Chemicals designed to kill or control pests and weeds can be highly toxic. Consumers should remember that most pesticides are weaker versions of the highly lethal organophosphate nerve gasses developed by the Germans during WWII and should be used with the utmost care.  Used incorrectly, pesticides can and do poison people and pets, kill beneficial bugs and taint soil and groundwater, experts say. So before you uncork your chemicals, experts suggest you ask several questions:

• What is your garden problem?

• Is it caused by a weed, an insect or a disease?

• Is the problem serious enough to require an herbicide or pesticide?

• If chemicals are needed, what's the safest one -- and when should you use it?

Fertilizers

In general, homeowners tend to use too much fertilizer, says Bob Nuss, professor of ornamental horticulture at Pennsylvania State University. He recommends a soil test before adding any nutrients.

For about $10, you can learn whether your lawn needs fertilizer -- and what kind. Soil kits are available at gardening centers and county extension offices.

Too much fertilizer can make grass grow too quickly and develop weak roots. Overfertilizing flowering plants will encourage them to grow more leaves -- and cut back on flowers.

Lawn fertilizers are often sold in combination with herbicides. The herbicides when applied improperly make their way to garden plants and trees causing poor or abnormal growth.  If you lawn is not infested with weeds avoid combination products if possible.

Pesticides, herbicides

If you decide to use a pesticide or an herbicide, experts say you should zero in on the problem: What kind of weed is it? What kind of insect? What kind of plant is the insect attacking? "One product won't control everything," Mr. Hamilton says.

Timing is also critical. Too early or too late in the season may not be effective. Some chemicals require that you water after applying them, while others need dry conditions.

The experts stress safety precautions when using any chemicals.

Consider planting pest and disease resistant plants whenever possible.  The variety of attractive resistant plants is increasing each year and there is a large selection to choose from.  This cuts the need for use of pesticides and fungicides.

Alternatives to chemicals

One way to cut back on herbicide use is to mulch, particularly annual plants, Mr. Nuss says. Mulching keeps down weed growth. Here's an example of nonchemical control for tent caterpillars, Mr. Hamilton says: "Just wait until all the caterpillars are in the tent and cut out the tent." Consider using ladybugs to rid your cherry trees, roses and other plants of aphids.  Praying manti kill many harmful garden insects.  These helpful insects can be purchased from most nurseries

Check with your garden center or extension office for more nonchemical alternatives.

Another approach: vigilance. Pick off that weed or bug as soon as it appears.

"Most folks say, 'I'll wait until next week,'" Mr. Nuss says, "and by then the weed has flowers and seeds."

Seeds of Safety

• Wear rubber gloves, long sleeves, long pants and eye protection. You may need a respirator, hat or shoes. Don't wear leather; it can absorb chemicals.

• Use separate spray systems for herbicides and pesticides so residues don't mix.

• Mix just enough pesticide for the problem. Dry pesticides can be stored for a season. Discard liquid pesticides through hazardous waste programs.

• Never carry a pesticide in your car's passenger area or next to food in the trunk.

• Store chemicals in original containers to avoid the possibility of poisoning.

• Use a 1- to 3-gallon hand-held sprayer, and use water to look for leaks or a plugged nozzle.

• Take special care when mixing pesticide. Have an adult nearby in case of accident. Follow label directions precisely. Have water, soap, towels and a hose handy in case of a spill. Mix in a well-ventilated area.

• Keep other people and pets away when applying a pesticide. The label will say whether to bar children and pets from treated areas.

• Clean the applicator and sprayer thoroughly after use. Rinse it with water and a small amount of detergent, then rinse twice more with water.

• When you finish cleaning up, wash your clothes (not with other clothing) in hot water with strong detergent. Take a hot shower; wash your hair.

Reading Labels

The Florida Cooperative Extension Service offers this explanation of toxicity warnings:

• Danger-Poison. These are the most toxic pesticides and should be handled with extreme care.

• Warning. These are moderately toxic and should be handled with care.

• Caution. These are slightly toxic materials that are still poisonous. Handle as you would any poison -- carefully.