Ask Mr. Smarty Plants

Although I've often seen the fluffy white evidence of the cochineal bugs on prickly pear cactus, I guess I hadn't really paid attention to when they were most abundant so I checked with an entomologist, Valerie Bugh, and here is what she said:

"The females live inside the white fluff and squishing their bodies is what produces the red dye. The highest concentration would be when the fluff is most numerous and each piece is rather big and clean looking, indicating mature females inside. Because it is a slightly water-resistant waxy substance, the white stuff tends to last a long time, but I've seen old remains that are dried out and wouldn't be very productive because the insect inside is dead. The time of year for the best harvests will vary depending on rainfall and temperature. If we have some very hard freezes, that will delay the insects' development, as will heavy rains or scorching summer droughts. I suspect that conditions are more important than dates."

Howard Garrett's The Dirt Doctor.com page on the cochineal says that females are harvested when they are about 90 days old.  Considering that mating and egg laying would happen when the weather is warm enough, say mid-March in the Central Texas Area, it would be early to mid-summer before the females would be ready to harvest (mid-June to late July).

You might be interested in reading about how modern cochineal farmers operate currently in Oaxaca, Mexico in the article, "Red Gold—Raising Cochineal in Oaxaca."