In chatting with one of the fellow gardeners at the Tipp City Community Gardens, we found little “piggies” all over her potato plants. I call them piggies because I used to rear them in a lab I worked at during my college days (University of Guelph, Ontario Canada). The adult female beetles would lay the yellow bullet shaped eggs all over the tubs of potato foliage I would grow in one of the greenhouses. Once they hatched, they would immediately start eating, and defecating!
They would grow through four larval stages getting to almost ½ an inch before pupating in the soil and emerging later as adult beetles. The larval stages can take up to 30 days and they would eat many tubs of potatoes (which I had to continually grow), defoliating them very quickly. Hence piggies!
In the garden, the eggs can be hard to see. The female lays them on the underside of leaves. The smaller instar larvae can also be hard to see resulting in them having eaten a lot of potato leaves before you may notice them. Once you do, it is best to control them quickly. You could hand pick them, but this can be tedious. I recommend treating them with the environmentally friendly product, Bull’s-Eye Bioinsecticde. This contains the active ingredient spinosad, which are beneficial metabolites from the bacterium S. spinosa. Bull’s-Eye will control both the larva and adult beetles effectively. Depending on the weather and pest pressure, multiple sprays may be necessary. It is also important to spray the underside of leaves to control the smaller larva.
If you are growing potatoes in your garden or community garden, there is a good chance you are going to get Colorado potato beetle “piggies”. Always inspect your garden for all kinds of pests. You can do this once a week and maybe more often as it gets a little warmer. This will help you eliminate any pests such as the “piggies” quickly before they affect your harvest.