According to an EPA report, over 5 billion pounds of herbicides and pesticides were used across the United States in 2007. The majority of that staggering number was used in agriculture to produce food products for human and livestock consumption. A study done by a USDA program found that 40% of fresh fruits and vegetables had residue of at least 2 pesticides. These pesticides and herbicides have been linked to illness, deaths and environmental die-offs for many years.
Many other non-chemical pest control measures have become better known in recent years because of public outcry for safer alternatives. Mechanical pest control, integrated pest management, poly-culture, crop rotation and “trap plants” are all options that have grown popular in the last decade.
When it comes to pests your first line of defense is prevention. Stopping pests before they become a real problem is the best, and most often times, the easiest choice. Growing in healthy soil, free from disease and “fatigue” can give your plants the boost they need to naturally defend themselves against pests. If you add soil or compost make sure it is free from seeds that will germinate and spread in your garden or lawn area.
Also, ensuring there are an adequate number of beneficial insects such as lady bugs and praying mantis before you plant will give you a head start in pest defense. Try to think of your garden in a “plant positive” instead of a “pest negative” way, by integrating proper crop rotation to prevent the spread of disease and to ensure your soil is healthy. You can also time your plantings to miss known hatching periods for certain insects.
Planting “trap plants” or “repellent plants” is also a good way to prevent pests from destroying your garden. Trap plants draw certain insects away from your crop; geraniums, marigolds, petunia and nasturtium all distract leaf-hoppers, aphids and beetles. Some trap plants also attract beneficial predatory insects. Additionally, repellent plants such as garlic, hyssop and rosemary deter aphids and cabbage moths, along with many other pests.
Another method that has become popular in recent years is poly-culture, the practice of growing many plants in a certain area. Using poly-culture you avoid the dangers of a single pest or disease wiping out an entire crop or planting. Additionally, with various plants in one space they can provide each other with needed nutrients. Poly-culture also provides habitat for a variety of beneficial insects, increasing biodiversity and healthy habitats.
There is also mechanical pest control which takes on two distinct forms. The first form is manually removing pests from plants; by trapping or picking. Most small scale growers find that some pests such as the tomato horned worm, snails or slugs are relatively easy to manually pick off plants. Using black-lights and flashlights many pests can be directly removed from plants, especially at night. While others utilize certain predator animals such as chickens, ducks, guinea fowl and even bats to manually get rid the area of unwanted insects.
Mechanical pest control also involves mechanical pesticides such as diatomaceous earth (DE). DE is the fossilized remains of diatoms, a type of algae with a hard shell. Diatomaceous earth works by absorbing lipids from the waxy outer skeleton of insects, causing them to dehydrate and dry out. Food grade DE can also be used as a natural wormer for livestock and animals. If you must treat with any type of insecticide, it should be a spot treatment, directed solely on the area that is infested. A broad spectrum spray over an entire “crop” should never be utilized as a means of pest control.
A key to pest control is to observe the pests that may be affecting your plants; decide if they are going to cause a catastrophic failure of your crop and then act accordingly. In nature, it is to be expected that pests will consume a portion of wanted plants; it is up to us to decide if it is an amount we can live with. Understand that biodiversity and healthy landscaping means a variety of “good” and “bad” bugs, and that accepting those differences and sometimes accepting losses for the sake of overall environmental health may be necessary.
Environmental Protection Agency. Pesticide Industry Sales and Usage for 2006 and 2007. Washington: EPA, 2011 http://www.epa.gov/opp00001/pestsales/07pestsales/market_estimates2007.pdf