Predator Mite (Amblyseius andersoni)

Amblyseius andersoni is a predatory mite that can be used in the control of a range of mite pests. This predatory mite is ideal for Cannabis, vegetables, hardy ornamentals and fruit crops, controlling red or two-spotted spider mite, fruit-tree red spider mite, and russet mites.

It is active at lower temperatures than other predatory mites, which means that it can be introduced much earlier in the growing season than some other predators.

Andersoni occurs naturally throughout Europe, including the UK and the Netherlands, and in North America. It is primarily found in areas of grape and apple production, but also in soft fruit, peaches, deciduous ornamentals and conifers.

They prey on spider mites of various species, but also feed on thrips and russet mites. They may enter diapause in late summer, but are active from early in the season, as well as tolerating high temperatures, provided the atmosphere is suitably humid.

Target Pest:
Broad Mites, Cyclamen Mites, Russet Mites, Two-Spotted Spider Mites, Thrip Larvae

Optimal Environment:

Working temperature range: 42-100°F
Relative Humidity: Higher humidity needed for environments with higher temperatures.
Amblyseius andersoni hatch at temperatures between 68° and 77° F. In cooler temperatures they will enter diapause to survive. Studies have shown that A. andersoni have a 100% diapause incidence below 18°C (64.5°F) when it is light for 10 hours or less.

Release Rates:

General release:

Traditional release rates are approximately 250 predators for every 6 ft. of crop row.


Adult female mites lay single eggs onto leaf hairs, and these eggs hatch after 2-3 days to become larvae.  As with other mites in the same family, these molt to produce proto-nymphs and then deuto-nymphs as they grow. All mobile stages are predatory, and will feed on eggs, juveniles and adults of spider mites. They are also able to feed on Eriophyid mites, commonly known as Rust or Russet Mites, which are tiny, worm like mites which can cause major damage on some crops.

As days become shorter and temperatures decrease in early autumn the mites will enter diapause, a state in which they can successfully survive winter conditions. They are reported to become active again as early as January, but this will be dependent upon ambient temperature and food availability.

Strategic Considerations:

Amblyseius andersoni is intended as a preventive treatment for spider mite and other mite pests, which is best used before pest populations have reached high levels. If pest mite populations are very high, and major damage is visible on the crop, use an alternative treatment such as biochemical miticide prior to the introduction of Amblyseius andersoni.