Potato beetles seem to be one of those "on" years-"off" years thing. Last year was an off year. I picked off maybe three or four and that was it. I start scouting early, thoroughly checking each branch for adults or those pink jelly-like larvae and picking them off before they hatch. Last year I found just those few adults and no larvae but then I had the potato patch a good ways from the previous year's.
There are three good articles in my Pest file about these critters and controlling them. Unfortunately the links are now kaput which is why I copy off and file this stuff. Here's one on control:
Control Colorado Potato Beetle with a Mix of Strategies
http://www.vegetablegardener.com/ite...-of-strategies
The feeding beetles lay yellow-orange eggs clustered in groups, usually on the undersides of leaves. The larvae, which look like fat, globular, slow-moving caterpillars, change from brown to pink as they grow, developing two rows of black spots along each side of their abdomen≥
Handpicking may be all you need to protect a small plot of potatoes. Picking is easiest early in the day when the beetles are cold and slow to move. Collect the beetles in a wide-mouth jar, coffee can, or deep baking pan, half full of soapy water. Place the container below leaves with beetles or larvae and shake the plant. The insects will fall into the container and drown. Larvae and egg masses also can be squished on the leaves. Gloves make the job easier.
Planting dates turn out to be important for the control of Colorado potato beetle. A standard recommendation is to plant potatoes very early (early April in Ohio, for instance), so that the plants bloom before June, and the beetle damage occurs too late to affect yield.
Planting potatoes in, or just beneath, a thick straw mulch has been shown to reduce damage from a number of potato pests, including aphids and flea beetles, as well as Colorado potato beetles.
Using row covers is a useful tactic. Anchor the covers securely into the soil because Colorado potato beetles are strong walkers and could move in under unburied row cover edges.
A number of new Btt (Bacillus thuringiensis tenebrionis) products have high selectivity for Colorado potato beetles and virtually no mammalian toxicity. Btt works best against the early larval stages, so must be timed properly. Wait until all the egg masses have hatched. You can tell because only the shells will be left, and little larvae will be crawling nearby. The larvae have to eat the Btt from the leaf, so coat the leaves thoroughly, especially the undersides.
Finally, here's an interesting control method:
https://www.rodalesorganiclife.com/g...beetle-control
Surrounding your potato patch with a plastic-lined, V-shaped trench can also reduce the number of adults that reach your plants in spring. As they emerge from the soil and head for the plants, they'll fall into the trench, where they can't get out, and you can destroy them.
Place row cover over the potatoes after planting and leave it on until you are ready to harvest.