Q & A

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Eric Vinje

Hi Alan –

Timing is often the trickiest part of releasing beneficial insects. While some predatory insects are able to survive periods without food, most need to eat constantly. Praying mantis can be released as long as some food is available. Keep in mind, the larger the population, the more effective the pest control.

Praying Mantis egg cases can take 6-8 weeks of warm temperatures, 65-75 degrees daytime, no lower than 45 degrees at night, to hatch. If immediate release is inconvenient you can keep the egg case(s) in the refrigerator for up to one week, but they must be in a ventilated container. DO NOT FREEZE.

To release, simply tie the praying mantis egg case(s) to twigs or branches about three feet above the ground. Birds and rodents will feed on them, so placing them in a container with holes large enough for the mantis to escape — 1/4 to 1/2 inch diameter — will provide protection. One case will yield approximately 50-200 nymphs.

To speed up the hatch, we recommend placing egg cases — still in the bag — on top of a refrigerator, or some place that is consistently warm, but not hot. Do not place them on a windowsill as temperatures fluctuate too much.

Note: The newly hatched insects squeeze through the egg sac, leaving it intact and disperse quickly without leaving behind a clue that hatching has occurred. It takes as much as five months for mantises to reach full size.

Hope it helps!