Organic Matters
Home Schoolers Creatively Combat Pests

Home is school for Mary Pavlinchak's three children, and their organic garden is a living science textbook. Inspired by their grandmother's love of gardening and her penchant for pointing out creatures and their interactions, Mary's children decided to dig up the lawn and get to work.

They hoped to bring to life their vision of an organic garden sporting flowers and a host of butterflies. Together, they dug up the whole lawn, discovering the scads of grubs that called it home. Armed with organic gardening books, the kids tried to create a healthy ecosystem and grapple with problems that arose. Grubs in the lawn? Water it with a detergent solution. Japanese beetles on roses? Concoct a spray made from blended hot peppers and onions.

But other, more complicated, challenges also arose. Although the children had their hearts set on a butterfly garden, butterflies, they realized, start as caterpillars. And they had already observed that the caterpillars munching on their garden plants were damaging the leaves. "The kids had to make a tough decision," notes Mary. "They decided to maintain a bird feeder filled with black sunflower seeds to attract birds who, they speculated, could help keep caterpillars in check. Together we discovered that it's all about balance."

Mary explains that the students derive many of their ideas for promoting garden health and controlling pests from their favorite book, Roses Love Garlic by Louise Riotte. They've tried burying banana peels near roses to supply potassium (as the peels decompose), using dissolved aspirin to prevent transplant shock, and using soap sprays and other concoctions to control pests. After experimenting with different approaches to pest control, the children decided that companion planting took less time and led to more interesting plantings. This approach involves planting certain crops near others to repel pests, attract (trap) pests, draw beneficial insects, or otherwise protect a crop. When the young growers planted chives and garlic near roses, the chives attracted aphids, who, the students inferred, seemed to prefer them to roses.

"It has been such a great learning tool because we try different strategies in the garden and work hard to learn and meet challenges," says Mary. "When we moved and had to start gardening from scratch in an entirely new environment, it was apparent how much they'd learned about how to go about solving problems and keeping plants healthy," she adds.

Buddy Plants, Beer, and Blenders: Testing Pest Control Wisdom
Ask gardeners about homegrown pest control and you'll get a slew of creative responses: beer-filled dishes to attract slugs, a spray of juiced bugs to deter insect relatives, marigolds planted to repel nematodes, and so on.

Such questions are rife with possibilities for student inquiry. Consider inviting your students to interview gardeners in your community and/or examine books or Internet sites in search of suggestions for companion plants and homemade pest remedies. Then set up some investigations to test their effectiveness. Be sure that your sleuths have observed carefully enough to see the creatures that are actually doing damage and have positively identified the culprits.

With companion planting, pest control is often the aim, but better space and nutrient efficiency can also result. Beneficial insects, such as ladybugs, depend on pests for nourishment. But when pests are in short supply, certain plants that offer nectar and pollen offer these good guys an alternative food source. Many of these are small-flowered plants that belong to the carrot and daisy families (anise, dill, fennel, yarrow, zinnia). Other companion plants repel harmful insects, or attract them and draw them away from your precious plants. The Canadian Bugline Web site (www.winnipeg-bugline.com/comp_pl.html) lists plants in these different categories. Consider experimenting with some of these in your classroom garden.

Following are some classic recipes for homemade insect sprays. Be sure to have students test such solutions on a few small leaves before starting a full-scale application and keep labeled containers tightly sealed in a safe place.

Homemade Soap Sprays. These can be effective against soft-bodied insects such as aphids. Dissolve 3 tablespoons of soap flakes (not detergent) in a gallon of water and spray on plants.

Herbal Insect Repellent. Gather leaves from tansy, lavender, and sage, which have strong insect-repelling qualities. You'll need an ounce of leaves from each plant. Place the herbs in a 1-quart jar and fill it with boiling water. Let it set until it cools. Or make an infusion by steeping the herbs in a jar of water placed in a sunny outdoor spot. Drain off the liquid and set this solution aside. Dissolve 1 teaspoon of soap flakes in 2 cups of water. Add 1/8 cup of the herb solution and mix well. Use a sprayer to coat all plant parts with the bug repellent.

Hot and Spicy Spray. Some gardeners combine hot peppers and garlic in a soapy solution. Puree two hot peppers and two cloves of garlic in a blender. Add 3 cups of water and 2 tablespoons of biodegradable liquid soap. Strain and fill a spray bottle with the solution.

Bug Juice. Although it seems a bit macabre, consider using bug juice to fight pests. Collect at least 1/2 cup of pesky insects and place them in an old blender with enough water to make a thick solution. Blend on high and strain out the pulp using cheesecloth or a fine sieve. Dilute at a rate of 1/4 cup bug juice to 1 cup of water, pour into a spray bottle, and apply to plants. (Some scientists believe that pheromones from the blended insects send a warning to their living relatives!)

Foiling Pests Naturally
Gardens, as dynamic ecosystems, offer countless opportunities for curious young observers to ask questions and pursue fruitful investigations. If we jump at short-term solutions to "problems" that arise, for example, by exterminating pests, children can lose the opportunity to develop, through careful observation and experimentation, a deeper understanding of the complex interactions among plants, insects, weather, soil conditions, and human horticultural practices. By understanding what makes our gardens and plants attractive to insects and diseases, and how to maintain plant and soil vitality, youngsters learn important lessons about how to work with nature to create a resilient system.

The best way to prevent pests from getting out of hand is to promote healthy plants and soils. Here are some tips for doing so.

If just a few insect pests show up on plants, students can continue to observe them, or simply pick them off and squish them. Remember, healthy plants and insect pests can co-exist. A few leaf holes aren't death for a plant. If students notice pests that seem on the verge of or in the midst of destroying entire crops, they might try knocking them off with a soapy water spray or homemade remedy, trapping them, or introducing beneficial insects.

Free Creatures for Young Scientists
Bothered by bugs? Irked by insect pests? Curious about who eats whom in your school garden? ARBICO, a company that supports environmentally sustainable gardening and farming, has offered to send selected beneficial insects and organisms -- green lacewings, ladybird beetles, praying mantids, beneficial nematodes, and others -- to classroom scientists who commit to using them to conduct investigations in classrooms, gardens, habitats, or greenhouses.

How To Apply
Have students brainstorm insect investigations appropriate for your growing context or a controlled indoor experiment. For example, Are ladybird beetles or a soapy water spray more effective for quashing an aphid infestation? Do lacewings "prefer" to dine on particular insects? (Mosquito problems? Design an experiment to test the effects of a benign bacteria on mosquito larvae and they'll send you the organisms.) Consider having students identify which garden creatures are actually damaging plants, then go to ARBICO's Problem Index (http://www.arbico.com) to locate beneficial organisms to request.

Finally, write a few paragraphs describing your students' proposed investigation design (or have your students do this) and send it to ARBICO via e-mail: rf@arbico.com; mail: ARBICO, P.O. Box 8910, Tucson, AZ 85738; or fax: 520-825-2038.

If your proposal is approved by the company, they will send you appropriate beneficial organisms, and instructions on handling them, free of charge. Don't forget to fill us in on your students' experiences.

Insects and Plants
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