Q. At desertusa.com, I found out that cochineal scale is what is affecting my prickly pear cactus. Although it described the problem, there was no explanation on how to get rid of it. I used a hose to wash off the scale. Do I need to do something else to save my cactus?
A. Cochineal scale is that white, fuzzy stuff that you see on some cacti. If you crush it between your fingers it has this very pretty dark red color that oozes from inside the white fuzzy stuff. The scale insect itself is under this layer of white fuzzy stuff where it lies protected and can feed on the plant juices. They can infest a cactus quite quickly and can be difficult to control. They can be quite a problem on the edible cacti.
Red dye coming from cochineal scale
In Mexico they use hard pesticides such as Sevin to help keep them under control. We usually just use a sweep nozzle on the end of the hose and turn it on all the way. A strong, steady stream of water will wash the scale off of the pads.
The problem is that once infested you will probably have to hose them off once every week or two during the summer season. During the winter season it is not as often. You are right, this is Cochineal scale. This is not the same scale exactly that is used for the red dye but a very close relative and still gives off a wonderful color that can be used for dyeing.