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It may come as a surprise to you that the beneficial insects in our yards and gardens far outnumber the pest insects. Some insects become a part of the life cycle of the plants by acting as pollinators, while others keep harmful insects in check by parasitizing or feeding on them. When we use chemicals to rid the garden of pests, we are also eradicating beneficial insects, and often create an imbalance that effects the overall health of the garden.
Using Beneficial Insects
A number of beneficial insects are available by mail order. Before placing your order, make sure you identify the target pest, because most predators or parasites only attack a particular species or group of pests. Your public library probably has a good book that will help you identify the culprits.
Once you release the insects, you'll need to give them a good reason to stay in your garden. Gardens Alive sells a combination beneficial insect and lure. Once the insects are released, the lure will help to keep them in your garden. This has worked great in my garden, and is a terrific buy.
| Beneficial Species | Pests Controlled | Tips |
|---|---|---|
|
Predatory Mite Geolaelaps | Fungus gnats, thrips | Release a minimum order to establish population early in the season. Good in greenhouses and on houseplants. |
|
Predatory Mite Phytoseiulus persimilis | spider mites | Release 2 to 5 per plant in greenhouses, on strawberries, or on houseplants. They need a moderate temperature (65-75 F) |
|
Western predatory mites Metaseiulus occidentalis | European red mite | Release 50-100 per tree to establish a population or 1,000 per tree to control outbreaks. Also good on strawberries. |
|
Aphid Midge Aphidoletes aphidimyza | aphids | Release 3-5 pupae per plant. Two releases may provide better results. Good in greenhouses, shade trees, orchards, gardens, rose gardens. |
|
Braconid Wasp Aphidius matricariae | Green peach and apple aphids | Buy the minimum order for a garden. Plant parsley-family flowers to provide a food source. |
|
Lady Beetles Hippodamia convergens | aphids | Release minimum order in greenhouses with screened vents. These insects will hibernate in cool greenhouses. |
|
Lacewings Chrysoperla carnea, Chrysoperla rufilabrus | aphids and thrips | Best to order eggs rather than adults. Distribute widely through the garden - 1 to 3 eggs per plant. |
|
Mealybug Destroyer Cryptolaemus montrouzieri | mealybugs | Use in greenhouses or cage them on houseplants. Use 2 to 5 per plant. Nymphs look like mealybugs. |
|
Minute Pirate Bug Orius tristicolor | thrips, mites | Release 1 to 3 per plant. Plant pollen-rich flowers to entice them to stay in your garden. |
|
Scale Predator Beetles Chilocorus spp., Lindorus spp. | soft scales | Use in greenhouses or on houseplants, citrus, or ornamental trees. Minimum order is sufficient for most needs. |
|
Spined soldier bug Podisus maculiventris | Colorado potato beetle, Mexican Bean Beetle | Release 5 per square yard. Look like stink bugs. |
|
Greenhouse Whiteflies Encarsia formosa | Greenhouse Whiteflies | Release 5 per plant at the first sign of whiteflies. Perform best in warm, bright environment. |
The following suggestions will go a long way toward helping you get the most of your hired killers:
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More Information
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