Did a lot of reading last fall about how to harvest and save my cocoons for this year. I shook and debris off them, gave them a rinse in very mild bleach solution then kept them cool in the garage fridge. When I put them out this spring only about 2-3 of the 100 cocoons hatched! What happened? Last year I had about 98% success rate.

Hoping someone more experienced can suggest what I may have done wrong. thanks

Harry