Weekend Gardener
6:41 pm
Sat April 30, 2011

The Weekend Gardener: Integrated Pest Management

Each month Gateway Greening community gardeners gather at the Schlafly Tap Room for Pints 'n' Plants, where guest speakers share their gardening expertise. The latest was from Small Farm Specialist Miranda Duschack, of Lincoln University Cooperative Extension, who shared her knowledge about Integrated Pest Management.

Duschack describes Integrated Pest Management as "a holistic practice of pest management that focuses on natural and cultural controls to contain or eliminate problems." Pests are defined as insects, weeds, and diseases. "Cultural controls" are practices such as using plants that are bred to be disease resistant, grafting heirlooms onto disease-resistant stock, and some of the more basic tips outlined below. For an in-depth definition of Integrated Pest Management (IPM), visit the EPA's website.

Oils, soaps, sprays, and clays:

  • "Horticultural oils," often cottonseed oil or  soybean oil, may be rubbed or sprayed onto plant leaves. Once the oil dries it creates a wax that prevents insect eggs from hatching. You may have seen neem oil in stores, which is not the same thing. While it is a naturally derived product, it is not recommended for use in IPM because neem is a broad-spectrum insecticide that will kill not only your unwanted insects, but also those beneficial insects that prey on all those aphids. Pyrethrum, made from a particular type of chrysanthemum, is also considered organic but is not recommended because it too is a broad-spectrum insect killer.
  • Using insecticidal soaps is recommended. These may be bought pre-mixed in stores or you can make a mixture yourself at home. One gardener found Castile soap in particular to be effective.
  • A kaolin clay solution sprayed on foliage and fruits is recommended for killing those troublesome Japanese Beetles. It will turn your fruits and vegetables white, however, which can be washed off most vegetables, but for fuzzy fruits like peaches it may be less desirable if you prefer your peaches to be, well, peach. A product called Surround uses kaolin clay and is readily available in stores.
  • Bacillus thuringiensis (or Bt) is a bacterium found in products with trade names Dipel and Duricide. It is not a broad-spectrum killer, so will protect most of your pollinators.

If you don’t want to mess with any of the products above, most of which require repeat applications after rain, you may prefer the following methods:

  • Using a “living mulch,” like clover, growing around and between, but not too close to, your vegetable plants will help distract aphids and provide habitat for beneficial insects like lady bugs and praying mantis.
  • Floating row covers: Use Reemay fabric and wire to make tents for your plants. Reemay will let in light and water, but not insects. You can keep the row covers in place until you see flowers on your plants, at which time you will want to allow pollinating insects to visit. By that time your plants will hopefully be strong and less likely to succumb to insects sucking their sap!
  • You can plant “trap crops,” which are meant to be more desirable to insects. ‘Blue Hubbard’ squash is a good bet for protecting your precious pattypans and other squash. Collard greens are a good at deterring moths from your cabbage. The Japanese eggplant ‘Vittoria’ will lure those pesky flea beetles away from other eggplants, especially the more traditional, round eggplants.
  • Finally, a trick to protect squash against vine borers is to burry the plant vines every five leaves or so to encourage stem rooting.

These are just a few of the pest management tips available. At the talk, Duschack also discussed controlling weeds and disease. To learn about these methods as well as more pest control ideas, visit:

In her professional role, Duschack provides one-on-one technical and educational assistance to small farmers and gardeners in St Louis City and County. Her clients are farmers who sell at market, community garden leaders, and backyard gardeners. Providing site assessments, garden designs, and research-based information on a variety of topics including pruning, IPM, growing vegetable crops, fruit trees, and honeybees, she also works with non-profit organizations and schools who are starting garden projects. To learn more about Lincoln University's Innovative Small Farmer's Program, you may visit their website.