By Susan Albert
Organic gardening can encompass a number of concepts, but most people agree that reducing or eliminating pesticides in the garden is a major component. In addition to aiding the environment, a pesticide-free garden allows a mini ecosystem to flourish.
But that doesn’t leave the gardener at the mercy of all possible ill wills. Healthy gardens don’t need a lot of chemical intervention if you follow commonsense practices.
Here are some tips to consider:
- Start with healthy soils. Enrich your garden with organic matter such as compost, aged animal manure, mulch, or peat moss. Healthy plants better resist disease and insect invasions.
- Rotate your crops so none grow on the same site for more than a year. This is an age-old method for controlling plant diseases by preventing the buildup of pathogens. Rotate vegetables as well as annuals.
- Choose disease-resistant fruit, vegetable, and ornamental varieties suited to your region. To identify the disease resistance, look for the letter codes on the seed package or plant. For example VFN means the plant resists verticillium wilt, fusarium wilt, and Southern root-knot nematode.
- Include native plants to supply habitat for birds, butterflies and their caterpillars, and insects. Natives reduce the water and fertilizer requirement, as well as the need for pesticides.
- Choose a wide variety of plant material to attract insect predators. Lady beetles, lacewings, and spiders benefit the garden, as do the insect parasites tachinid flies, and braconid and ichneumonid wasps. Insect predators do the work of pesticides.
- Select plants well adapted to our area such as those listed as Oklahoma Proven or Texas Superstar. Pictured is an oakleaf hydrangea (Hydrangea quercifolia) at the Tulsa, Oklahoma extension office. On the Texas A&M Extension website, you can select plants from its Earth Kind database that have been rated for heat tolerance, drought tolerance, pest tolerance, and soil and fertility requirement based on region.
- If you like roses, choose disease-resistant varieties you don’t need to spray for black spot and other fungal diseases. Examples are Knock Out or Earth Kind roses. Many new rose introductions are disease resistant, especially shrub roses.
- Marigolds can assist with nematode control, but only as a cover crop. You need to plant marigolds at least two months before the desirable plant, and anchor the desirable plant where the marigolds were planted. The marigolds contain a substance that acts as a nemacide and reduces nematodes’ numbers. The effect lasts only about a season, and nematode populations increase again over time.
- If you own a sweet gum tree, with its spiny seed balls, put them to good use. Spread them under your hostas; the slugs and snails find them too sharp to traverse.
- Remove and dispose of diseased plant material as soon as you notice it. Toss it rather than compost.
- At the end of the season remove plant debris to discourage overwintering disease organisms and insects.
By following some of these cultural practices, you can reduce and possibly eliminate pesticides in the garden.