Toby Tobin's 5 tips for using lawn and garden chemicals

OVERLAND PARK, Kan. - The first sign of a dandelion sends some people straight to the weed and feed aisle of their lawn and garden store. Expert Toby Tobin says they're the same folks who might use four tablespoons of a lawn product when the directions call for two.

"They over kill," said Toby, local lawn and garden expert and host of his own radio show. "People get confused when it comes to chemicals.

From crabgrass and dandelions to outside insects and indoor ants, Toby shares a few lessons to help the home green thumb wade through the chemical confusion.

1) Never spray until you see a problem, and then choose the right remedy

Whether its weeds or insects attacking your lawn or garden, Toby says it is important to take the proper action when you "see" a problem. One mistake people make is acting too soon and thinking the chemicals are preventative when they are not.

"When you spray a plant with an insecticide or fungicide, it's only going to be effective for five or seven days," explained Toby. "So, wait until you see a problem."

Making a weekly inspection of your garden is the best way to stay ahead of common plant pests. Likewise, identifying the weeds in your lawn along with the proper control takes diligence combined with a swift response. Toby says a common mistake people make is using weed and feed to kill dandelions.

"A weed and feed does not prevent dandelions," explained Toby. "People confuse it with crab grass control. It kills only what is actively growing at the time you apply it."

When the first few yellow weeds bloom, Toby says to reach for a liquid weed killer to spot spray. Toby is a fan of insecticidal soaps. Gardeners have used soaps since the 1800s to combat pests on plants. Back then it was commonly made of whale or fish oil. New Mexico University Extension Entomolgists say recent tests show Ivory Liquid dish detergent is effective and easy to mix using a 1 percent to 2 percent solution.

Whatever brand you choose, Toby says to spot spray first and apply a separate fertilizer or feed to your entire yard.

"A good thick lawn is your best weed control," Toby added. To break out the weed and feed, he says your lawn should be at least 40 percent full of dandelions.

2) Use the least amount of chemicals required to do the job and apply correctly

Once you identify your problem and solution, Toby teaches that it's best to treat using the smallest amount of chemical to do the job.

"Follow directions," said Toby. "If a product calls for one tablespoon per gallon, don't do two."

Toby says people think that if a little works, then a little more might be better. In reality, adding to the mixture doesn't help and can sometimes harm your plants. Toby also points out that using extra chemical when you don't need it is a waste of money.

Another Toby tip when applying chemical sprays is to do it late in the day when the winds die down and good insects go to bed.

"Beneficial insects they're at home sleeping after dark," said Toby. "They move back to home and aren't on that plant so you can spray at evening right at dark or at dusk and it's not going to hurt beneficial insects."

If weeds are the problem, it's equally important to apply the chemical correctly. The weed control chemicals need to stick to the leaves in order to work so Toby recommends waiting to treat your yard until there is dew on the ground or lightly watering before you spray or spread.

3) Choose chemicals with high LD50 (lethal dose) ratings – the higher the number, the safer the product

The Environmental Protection Agency (EPA) has a rating system that can be confusing to consumers. On each chemical label is an "LD50" number. It is the government standard that warns consumers about the toxicity of the chemical in relationship to humans. The LD50 is stated in milligrams (mg) of pesticide per kilogram (kg) of body weight. An LD50 represents the individual dose required to kill 50 percent of a population of test animals such as rats, fish, mice, or cockroaches. The higher the LD50 value the safer the chemical. This labeling is the most important thing to watch for in selecting a safe pesticide or insecticide. Toby adds that organic does not necessarily mean safer.

"Rotenone is organic but is much more toxic than some synthetic products," warned Toby. The botanical insecticide is found naturally in plants growing in Asia and South America. It is considered harmless to plants, but highly toxic to fish and insects like beetles and caterpillars. It kills on contact as well as working through their stomachs.

4) Wear protective clothing

When handling chemicals like rotenone, the EPA recommends wearing a mask to protect your respiratory system. Toby remembers his horror watching a friend treating his tomatoes with rotenone wearing shorts and a t-shirt. Dust was flying everywhere.

"I said, what are you using?" remembered Toby. "He said, oh, it is okay this is organic."

Toby quickly told his friend how to read the label and explained the LD50 rating of 75 on his container of rotenone. Toby then recommended a synthetic chemical that used an organic component called pyrethrum with an LD50 rating of 1500. Pyrethrum is also botanical, but much less toxic. It targets insects paralyzing them. When mixed with synthetic chemicals, the affects of the pyrethrum lingers making it more effective in killing insects, but it does not the boost the toxicity.

Toby said his friend promised to wear long pants and sleeves the next time he used a chemical.

"A man-made chemical can be a lot safer," explained Toby. Even with long pants and sleeves, some people who are sensitive to chemicals should not handle them at all.

5) Never use spray pesticides inside.

Toby is not a big fan of using bug sprays indoors.

"I never recommend any pesticides inside the home," said Toby who points to EPA studies critical of indoor pollution that can be two to 10 times worse that outdoor pollution. "When you spray that just makes the insects move somewhere else."

Toby's tip to get rid of indoor bugs is an ant bait that's been around for decades called Terro. The liquid goes on little pieces of cardboard that you place in the ants' path.

"Ants are looking for food or water," said Toby. "Terro ant bait is boric acid powder and sugar. It's sweet and so the ants are attracted to it. They pick it up and take it to their colony where it kills them."

The process takes a few days, but then the ants are gone. The bait is safer for children and pets than bug sprays.

Toby does recommend spraying outside the foundation of the house and three or four feet into the yard to prevent insects from coming indoors. Toby does it spring, summer and fall.

Want more "Tips from Toby"? Watch NBC Action News every Saturday morning and watch past segments on

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