>Next: Applying Garden Chemicals
IPM: Integrated Pest Management
On this page, learn the progressive-step method of controlling vegetable pests and diseases called Integrated Pest Management (“IPM”), including:
-
- Controlling pests and diseases while protecting the environment.
- The behavior of insect and other vegetable plant pests.
- How Integrated Pest Management works to control vegetable pests.
- The four steps of an effective pest management and control program using Integrated Pest Management practices.
- Least-toxic control measures for vegetable pests and diseases.
About Pest and Disease Control
Integrated Pest Management, or IPM, controls outbreaks of pests and protects the environment. It works with nature to keep vegetable plants healthy. Protecting the environment should be a priority for every vegetable gardener seeking healthy, tasty crops.
Understanding IPM
Many studies show organic growing methods reap produce and fruit nearly equal in quality and quantity to those drawn from fields treated with pesticides. How can this be so? The answer lies in the dynamic of insect and bacteria populations.
As for other animal groups, insects are divided into two large groups: the herbivores—those that eat foliage—and the carnivores, which eat other insects. For any given population of herbivores, a smaller number of carnivorous predators exist and keep the plant eating population in balance.
Pests that harm vegetable plants are drawn from the more numerous herbivore group. These plant-eating insects reproduce quickly because their ranks are easily depleted by predator insects, which reproduce more slowly.
When pesticides are applied to a garden with an insect population and a full range of other living organisms, most of the plant eaters and nearly all of the predatory insects are killed. Beneficial and harmful bacteria living in the soil also die, faced with no hosts to supply them food.
Of the small number of each type that remain, the herbivores bounce back faster than the carnivorous insects, since very few predators survive to stem their tide. Even more pesticide is needed to control this population boom, starting a chain reaction requiring more and more pesticides. The natural balance that once held the two populations in check is destroyed.
How IPM Works
Scientists studying these insect populations believe they know the best ways to control infestations of harmful insects and take advantage of the natural dynamics of insect populations. The U.S. Department of Agriculture (USDA) recommends controlling pests with “Integrated Pest Management,” or IPM.
Using IPM, a small amount of residual crop damage occurs, but surprisingly little more than would be the case for fields that were treated with waves of pesticide applications.
At its core, IPM recommends a series of progressive steps depending on the severity of the infestation until it is controlled.
IPM’s Steps For Pest Control
The first step in mounting an IPM defense is planting healthy vegetables that are naturally resistant to common diseases and some insects. Healthy plants are best able to fend off early attacks by insects until predator populations can bring them under control.
Next, keep your plants and soils healthy by employing good watering, fertilizing, and cultivating practices.
Promote beneficial soil bacteria by improving the conditions they need to survive by adding organic material to your garden’s soils each year before planting and limiting to the essential any use of control applications.
Separate your plantings by dividing large numbers of plants into groups for different spots in your garden. Insect pests are specific to each species, and separation limits large populations.
The third step is regular scouting of your garden for pest infestations, disease infections, and general cleanliness.
Inspect your garden at least weekly, looking closely for signs of insect activity or disease. Finding an infestation or infection is the best way to limit its spread. Eradicate all weeds, since native plants are often preferred hosts to pests and diseases. Turn over leaves and look for chewed or rasped stems.
Most infestations can be controlled easily when found early. If you find pests, pick them from the plants or wash them off using a spray of clean water. Prune away infested foliage and destroy it. Seek out egg cases and remove them. If non-toxic sticky panel traps or baits are available for the pests you find, place them nearby but at some distance away from the infested plants.
Sometimes, stronger treatments are necessary.
When an infestation proves resistant to hand controls, apply minimally toxic controls such as horticultural oils, soaps, or insecticidal soaps directly to the pests. Avoiding broadcast spraying of large areas to preserve natural predators.
As a last resort for very stubborn infestations, apply botanical pesticides such as neem oil, rotenone, or pyrethrin according to their package directions, choosing a control that specifically names the insect and edible plants you intend to treat. Observe carefully and completely all label cautions, including those specifying how long one must wait to harvest edible fruits, produce and greens after application of the control agent.
IPM Means Good Outcomes
Integrated Pest Management, or IPM, is employing common-sense garden health practices derived from rigorous scientific research.
Its step-by-step approach makes far more sense than quickly reaching for pesticides or other controls at the first sign of an outbreak.
IPM is also a better choice than ignoring early evidence of pests and diseases or abandoning your garden when they overwhelm your vegetables.