Integrated Pest Management
As a gardener, it is inevitable that you will have to deal with pests trying to eat your plants. However, spraying pesticides to kill these pests can cause as many problems as the pests themselves. Scientists have developed a plan of attack for gardeners called Integrated Pest Management (IPM). This method relies on cultural and biological controls for pests and only uses chemical controls when these have failed. This reduces the impact on the environment and is safer for you and your family.
Cultural controls are things you put in place before planting and as you plant. For example, it is important to plant varieties of plants that are immune to common diseases in your area. Hybrid tomato plants usually carry a resistance to fusarium wilt, where as heirloom tomato plants are usually very susceptible to it. If you know you have problems with fusarium wilt in your area, pick a hybrid tomato variety that is resistant to it.
When planting transplants, it is important to make sure that the plants you bring home are free of pests. Just as important is using sterilized soil and containers when starting seeds. Soil can be sterilized by being cooked in the oven at 200 degrees F for 30 minutes, while containers can be sterilized by being washed in a bath of one part bleach and nine parts water for ten minutes. Be sure to rinse the containers well in clean water before planting anything in them.
Finally, cultural controls refer to using the best practices known to prepare your garden site, irrigate it, fertilize it, and maintain it free of weeds and other problems. The best way to learn these practices is to attend programs put on by your local Extension agency. Most of them have websites with publications on the proper way to set up a drip irrigation system, prepare a site for planting, and other basic practices. Your tax dollars have already paid for this information so be sure and take advantage of it.
Biological control consists of using predators that would naturally occur in the environment to eliminate the pests on your plants. For example, if you have aphids, lady beetles will naturally come and eat them if the lady beetles are present. If you spray the aphids, you will kill all the lady beetles as well. Next time aphids show up, they will be that much worse because there are no natural predators to kill them.
One of the features of IPM is called the economic threshold. It refers to the level of pests that negatively impact the crop. Sometimes this is how many pests it takes to eat enough of a wheat crop to make it cheaper to treat the crop with chemicals than to feed the pests. Sometimes it is how many bugs it takes to damage your flowers enough to upset you. Below this economic threshold, you tolerate the pests. Above it, you take some direct action to kill them.
This is where the chemical control comes in. Sometimes the action you take is introducing biological controls such as Bacillus t. to kill your caterpillars. Sometimes it is spraying a pesticide to kill the aphids on your roses.
When you do use chemicals, you do not treat the entire garden. Only treat the effected plants. Not only is this cheaper and less toxic, it leaves a reservoir of beneficial insects that will move in when the chemical wears off so your pests don’t rebound and take over the plants again.
Integrated Pest Management uses cultural, biological, and chemical controls to eliminate pests in the garden with the least harm to the environment. This is a win-win solution for everyone -- except the pests, of course.