Predatory mites
categories: Natural Enemies Other Natural Enemies
last review date: 2025-08-23 05:40
Photo by: D.G. James
Biology
Predatory mites are among the unseen and invariably unsung heroes of the home garden. A typical garden in the Pacific Northwest not treated with pesticides will be home to dozens of species of predatory mites living on leaves, in trees or on the ground. They prey mainly on plant-feeding pest mites but also consume insect eggs and thrips.
A hand lens or microscope is usually needed to have a good look at predatory mites (1/50 inch in length) but most move rapidly thus may be seen by the naked eye as fast moving ‘dots’ on the undersides of leaves. The most important group of predatory mites, known as phytoseiids, are extensively used in biocontrol programs against spider mites in agriculture.
A healthy home garden population of phytoseiids will go a long way to ensuring spider mites are not a pest problem on plants. Phytoseiids are excellent predators of a range of plant-feeding mites. If pest mites regularly cause damage in your garden, then you likely have few phytoseiids.
Predatory mites may be purchased from biological control suppliers, but it is best to attract and conserve locally adapted populations by restricting pesticide use. Plants with leaves that have hairs, chambers or pits on the underside are often favored by predatory mites because they provide shelter.
Prey or Pest Targeted
- Mites, scale insects, insect eggs, nematodes
Attracting and Keeping Natural Enemies
and Pollinators in Your Yard and Garden
- Native plants provide essential resources.
- Native flora also provides natural overwintering sites.
- Natural dispersion from nearby habitats ensures visitation.
- Some kinds of beneficial insects predatory mites are commercially available.
- Avoid regular use of synthetic, broad-spectrum pesticides.
- Infrequent use of certain narrow-spectrum pesticides is more compatible with some beneficials.
- Extensive lawns are also not conducive to attracting beneficial insects.
Management Options
See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- None recommended
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Evidence of noncompliance may be reported through your local Extension office.