Pictured top: Two-Spotted spider mites and a round pest mite egg
Pictured right: Spider mites and extreme webbing
Two-spotted spider mites are one of the most common pests found in greenhouses and gardens.
For control, we recommend two different species of predatory mites: persimilis and fallacis, and also the small beetle Stethorus.
Persimilis is the main predator of spider mites and is the only one that will go directly into the webbing to eat them. They do best at a humidity of at least 60%, or you can help by misting your plants twice daily to keep the environment humid (pest spider mites love dry conditions). It may be necessary to reintroduce them after 7-10 days if you're dealing with a heavy infestation, or conditions are sub-optimal.
Helpful Hint: One thing to be sure of before introducing persimilis (or any other type of beneficial bug) is that you have no pesticide residues on your plants. If you have used a pesticide even 4-8 weeks earlier, you need to tell us to see if you will have created a hostile environment for the beneficials to work well in.
Fallacis are the best predator of spider mites if you seek to be preventative. They can also be introduced at the same time as persimilis, and after the persimilis have done their work, the fallacis will stick around on your crop feeding on pollen as well as helping to subdue future outbreaks of pest mites on your plants. They can even be introduced on "clean" plants. Fallacis has a varied diet that includes bamboo mites, spruce spider mites on a wide variety of crops from field berries to container nurseries and greenhouse vegetables.
Stethorus are a small black ladybird beetle that are a great predator of pest mites as well. They have two advantages over the predatory mites: they are good flyers, and they are more tolerant to lower humidity.
They are meant to be used as "hot spot" treatment, alongside the mite predators above. They are expensive to rear so realistically are to be used as a supplement as these predators will fly freely to find new mite spots.
Click here to go to Applied Bio-nomics technical manual
Hot Mites (N. fallacis):
500 Mites (22701): $45.00 on vermiculite. suited for areas up to 2500 sq. feet
1,000 Mites (22702): $65.00 on vermiculite. suited for areas up to 5000 sq. feet
Buy 3 or more: $55.00
1,250 Mites (22703): $84.00 on bean leaves. - suited for outdoor areas up to 5000 sq. feet
2,500 Mites (22704): $115.00 on bean leaves - suited for outdoor areas only 5000+ sq. feet
Mighty Mites (P. persimilis):
1,000 Mites (22750): $56.00 on vermiculite (for areas ~500 square feet)
Buy 3 or more: $40.00
2,000 Mites (22751): $76.00 on vermiculite - smaller "hot spot" vial (for ~500-1000 sq. feet)
Buy 3 or more: $60.00
3,000 Mites (22752): $92.00 on bean leaves (contain pest spider mites as food during transit)
Buy 3 or more: $75.00
Stethorus (Stethorus punctillum)
50 Beetles (22763): $72.50
100 Beetles (22764): $99.50
SMALL: $160.00 (22810)
Contains: 1,000 Persimilis
Combined value of $173.50
REGULAR: $195.00 (22812)
Contains: 2,000 Persimilis
Combined value of $220.50
Pictured top: Label of the Mighty Mites 3,000 mites on bean leaves
Pictured middle: The distinctive orange colour of persimilis (Mighty Mites)
Pictured bottom: The black Stethorus beetle