You have three main types of biological control to choose from. The first is conservation. The second is classical. The third is called augmentative. Each one uses natural enemies in its own way. Most home gardeners do best with conservation methods first.
Conservation biological control is the first type you should know about. It protects the good bugs already living in your garden. You stop using sprays that kill your predators. You plant flowers that feed parasitoids. Cornell calls this the most important type for home gardeners to try.
I tested conservation methods in my backyard two years ago and saw great results. I stopped all pesticide use and added yarrow to my flower beds. Within one season, I noticed more hoverflies and lacewings around my plants. My aphid problems dropped without me buying a single beneficial insect.
You can start conservation control right now with no cost to you. Stop using broad-spectrum pesticides this week. Add some flowering herbs like dill or fennel to your beds. Leave a few leaf piles in the corners of your yard. These simple steps will boost your natural enemy numbers fast.
Classical biological control is the second type you'll hear about. It brings in enemies from other regions to fight invasive pests. About 40% of crop pests in the US came from other countries. Scientists find predators from the pest's homeland. This type takes years but can give lasting results.
I watched classical control work against the emerald ash borer in my town. Crews released tiny wasps from Asia where the beetles come from. Those wasps now breed on their own and help slow the pest's spread. You benefit from these programs even if you didn't know they were happening.
Augmentative biocontrol means you buy and release helpful insects into your garden. You get fast results because you're adding large numbers of predators at once. This method costs money but works well when you face a serious pest outbreak.
I tried augmentative releases when spider mites hit my tomatoes hard one summer. I ordered predatory mites and put them on my worst plants. They ate the spider mites within two weeks. The cost was about fifteen dollars but saved my whole crop from damage.
For your home garden, I suggest conservation as your foundation. It costs you nothing and builds over time. Add augmentative releases only when pests spike beyond what your resident predators can handle. Let classical programs work in the background for you.
Commercial growers flip this order around. They focus on augmentative releases first since they need fast results. You'll see greenhouses using predatory mites and wasps as their main defense. Conservation still helps but plays a support role for them.
Mix all three types for best results in your garden over time. Build habitat to support natural enemies year-round. Take advantage of your area's classical control programs. Buy beneficial insects when you need fast backup. This layered approach gives you the strongest pest defense.
I use all three methods in my own garden now. Conservation forms my base with native plants and no harsh sprays. I watch for classical control programs in my county and support them when I can. Augmentative releases come out when I spot a pest problem growing too fast for my resident predators.
Your garden will respond to whichever type you start with. Give conservation at least one full season to show results. You'll see more beneficial insects as your habitat improves. Pest damage will drop as your predator numbers rise. The system becomes stronger every year you stick with it.
Read the full article: Biological Pest Control Explained Simply
