Chemical Free: A Guide to Organic Garden Care Without Pesticides
By Richard Gillespie
Thick, lush, and weed-free is your ultimate goal when it comes to your garden and lawn. It’s tempting to use pesticides and fertilizers - until you consider the harm chemical products can do to the environment.
Natural pest control and organic fertilizers make your garden eco-friendly and promote biodiversity. Organic pesticides are safer than chemicals, especially when you have kids and pets running around in the yard. Dogs and cats chewing on plants and grass are less likely to become ill from organic pest control.
Most organic pesticides come from natural ingredients, but they still contain some chemicals from botanical and mineral sources. Because these “natural” chemicals break down fast, they are less threatening to the environment.
Organic pesticide ingredients may include lime, sulfur, soap, and hydrogen peroxide. Commercial products certified organic must be labeled as such.
BT. Short for bacillus thuringiensis, this bacteria kills bugs that ingest it. BT targets larvae of pests without hurting more beneficial insects. It’s effective on cabbage worms, armyworms, tomato hornworms, and other vegetative-chewing insects. It’s available in powder and liquid forms.
Insecticidal soap. As one of the better organic pest control options for aphids, insecticidal soap also kills soft-bodied insects like syrphid flies, lacewings, and ladybugs. Solutions can burn plant leaves if not mixed correctly. (Test with a light application before spraying whole plants). Insecticidal soap works on bean beetle larvae and young squash bugs, too.
Pyrethrin. This organic product (from chrysanthemum flowers) is a broad-based insecticide that kills just about everything. But because it kills “the good bugs” and can harm pets if ingested in large doses, use it sparingly and only when truly necessary.
Diatomaceous Earth. Diatomaceous earth is made from fossilized remains of tiny aquatic organisms. The result is a natural substance called silica which accumulates as deposits in lakes, streams, rivers, and oceans. The product kills snails and slugs.
Kaolin Clay. Apply this fine white mineral powder (mixed with a drop of water or soap) to leaf surfaces. It repels beetles and other insects by making them feel as if they’re walking on a “sheet of glass.” If Kaolin clay sounds like something you’d use in your skincare routine, it just might be. Kaolin is also used to make china and porcelain.
Neem Oil. This is one of the most effective botanical pesticides for soft-bodied insects. Use with caution -- neem oil can also kill the larvae of beneficial insects.
Horticultural Oil. Similar to neem, horticultural oil covers and suffocates bugs. It’s stronger than insecticidal soap, so read the package directions carefully.
If you’re an avid Do-It-Yourselfer, homemade bug repellent recipes are generally simple to use, but they take some time and effort to mix and apply correctly.
Vegetable Spray. Kill off aphids, thrips, and mites with a mixture of vegetable oil and mild castile soap. Blend one cup of oil with a tablespoon of soap, cover the container and shake thoroughly. Before spraying on plants, add two teaspoons of the oily mix to one quart of water. Shake well. Spray directly onto the plants and say goodbye to bugs. (Oil coats the insects’ bodies, keeping them from breathing).
Garlic Spray. Garlic may be a necessary ingredient for that perfect spaghetti sauce, but the odor can be offensive to some -- especially insects. With a blender or food processor, mix up a pungent spray with two whole bulbs of garlic (not small cloves) and a small amount of water. Let the mixture sit overnight (you may want to take it outside so as not to stink up the whole kitchen). Strain the garlic into a quart jar with a ½ cup of vegetable oil, a teaspoon of mild liquid soap, and enough water to fill the jar. Mix one cup of the recipe with a quart of water. Spray infested plants as needed.
Chili Pepper Spray. Much like garlic, chili pepper spray is effective on a variety of unwanted pests, and you can make it with powder or fresh hot peppers.
Before you start, put on a pair of disposable gloves. hot peppers have a natural chemical called capsaicin that can burn your skin. When handling chili or any other type of hot pepper, keep it away from your eyes, mouth, and nose.
For a chili pepper spray mix from powder, mix one tablespoon with a quart of water and three or four drops of mild liquid soap. Put it in a spray bottle, shake well, and apply to plant leaves.
When using fresh peppers, blend ½ cup with one full cup of water. Place it on the stove and bring to a full boil. Let sit until cooled. Strain out the chili pieces, add a few drops of liquid soap, and place it in a spray bottle.
DIY Sticky Trap. Make sticky traps with brightly colored materials coated in goo. Much like the hanging fly tape available in stores, yellow is best for attracting most insects (but red also works for some kinds of bugs).
Paint a piece of cardboard, plastic, or wood. Choose a slick and sticky substance that will stay gooey, like honey, petroleum oil, or non-drying glue. Smear the gunk onto the sturdy yellow object and place it by your plants; insects will come to stay. Clean and re-use, as needed.
Organic Lawn Care
The first step to going organic is a soil test to determine what, if any, nutrients are needed for healthy growing plants. In Michigan, for example, grass thrives in slightly acidic soil with a pH from 6.2 to 7.0. Soil pH below 6.2 needs lime to cool the acidity. If the soil is alkaline (pH above 7.0), add sulfur to lower the number.
Another example? Soil that lacks sufficient calcium can be amended with gypsum. If it’s low in magnesium, a dose of mineral langbeinite should do the trick.
You can order a soil kit through the Wayne County Extension. Dig up samples from several areas of the lawn -- two cups of soil total.
Before buying soil additives, be sure to look at the package to determine if they are organic. And before applying additives, cut the grass to about 2 inches. Remove weeds and thatch (a place where pests like to hide.)
Safety in Organics
Organic pesticides, fertilizers, and weedkillers prevent chemicals from flowing through watersheds into streams, lakes, and rivers. They also protect the good bugs - the ones that eat the lawn-destroying insects and pollinate our plants. By going organic, you let Mother Nature work for you and protect the Earth for future generations.
Richard Gillespie is an exterminator whose interest in household and landscape pests began as a child when he would crank up the radio to hear “I Don’t Like Spiders and Snakes.” He prides himself on practicing humane and eco-friendly pest control - unless he finds a rat. Then, all bets are off.