Even growers with small gardens should consider Bt. And if Bt. is sprayed frequently it can virtually eliminate the problem. Start with spraying as soon as there is anything in the garden for the beetles to eat and spray every 10 days to two weeks. Bt. is a bacteria not significantly different than the ones that make yogurt. If adult beetles are causing too much trouble, Bt. will not help until the next cycle has come around.
Flea beetles can also make so many pinholes in leaves that the overall yield suffers greatly.
The health of the vines has a great deal to do with how much interest flea beetles have in a plant. So the best prevention is total soil fertility. If you are having flea beetle problems, you should consider improving your soil's fertility next year. Normally, seven or eight weeks after planting, the earliest varieties are blossoming. This signifies that early potatoes may be ready, so gently poke into a potato hill by hand to see what you can find while making as little disturbance as possible.