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Joined: Sun Mar 27, 2011 2:22 pm
Location: Orange County, California

Praying mantis eggs

I wonder if anyone can tell me how long and what conditions it takes for a praying mantis egg sack to hatch.

Last year we that the opportunity to watch a praying mantis go full life cycle from little baby that I found on my giant sunflower all the way to female adult who attracted a male (I even saw them mate) and then put a eggsack onto one of the smaller palm trees near my vegetable beds before she died a few weeks later. We would have loved to see that eggsack hatch, unfortunately the weather here has been very unpredictable with late rains and winds.
Friday too weeks ago a especially strong downpour and storm knocked over the palm tree and somehow the eggsack got lost.

When I went to the nursery last week I saw they were selling praying mantis eggsacks so I bought a container (2 sacks). The lady at the nursey told me it takes about 10 days of mild to warm weather. but she couldn't really tell me what temp mild to warm means.
Last week we had temps up to the high 80s so I didn't want to take a risk frying them. But I was going to put them out today or tomorrow hoping they might hatch next week while the grandparents are visiting. Temps are supposed to be high 60 to mid 70s for the coming week but some showers (nothing too big just about 1/2 an inch) are predicted for tomorrow.
Should I put the eggsacks out? Wait until the rain passed? Wait for warmer weather?
Any advice would be greatly appreciated.

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Joined: Tue Apr 24, 2012 12:46 pm
Location: California

The ideal temperature range for releasing Praying Mantids is between 70-90F, it NEEDS to be warm for them to hatch. From then on it takes about 5 months to hatch. If you want to prevent hatching, you can store the eggs in a refrigerator but I would suggest releasing them before August if you want to give the baby Mantids time to mature and reproduce before colder weather comes your direction. I would definitely wait until the rain has passed too. It is also very hard to tell when the egg has hatched as it does not change shape or form, so maybe they DID hatch? Who knows. Hope this helps.

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Joined: Thu May 01, 2008 7:21 pm
Location: Zone 6, NJ (3/M)4/E ~ 10/M(11/B)

Haha I was going to say it needs to be about 80+...°F. When it's good and hot to go sleeveless and really wish you were wearing short pants, they come pouring out.

I currently have something over a dozen ooths all over my garden. it seems like everywhere I turn, there's another one. I had to be very careful during spring clean up.

We had a heat wave last week of upper 80's and I saw that some of the ooths showed signs of hatching -- not complete but at least some of the eggs decided it was time. Yesterday, I was weeding and a tiny, still tan-colored mantis baby scuttled away. :D

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Location: TN/GA 7b

They eggs are laid in the fall and over-winter. So it takes months to hatch counting the over-wintering. But I don't believe that it takes five months AFTER it warms up. I think they appear quite soon after temps get consistently in the mid-70's. I usually have baby praying Mantis in my garden starting sometime in May.

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