Find a farmer and get some Desis from them, or buy a big jug of it for yourself. 1/4 tsp of Desis per litre of water will kill all insects. I spray the corn when it is knee high, getting into the new growth with a spray of Desis. Once again, I spray the corn a few weeks later, getting the tops of each corn silk. This year I only sprayed the corn once, at knee height, and only found 2 or 3 cobs with a corn borer in the 3 long long rows of corn in my garden on our acreage.

Desis works wonderful for aphids on the roses and potato bugs on potatoes. I had a little green worm every year in a row on the gooseberries... used Desis in the spring, just at the onset of the worms 2 years ago, and I had no worms last year and only a few this year. I guess the worm/moth overwintered on or near the gooseberries cause I haven't seen it much since I sprayed the Desis on the gooseberries.

I do not let the Desis freeze in the winter and I mix up a small batch each time I need some... shaking it up well before spraying.

Using potato dust is very expensive and you may as well buy your potatoes instead.

You should always properly handle the Desis. Remember that it is a very strong chemical, but very very effective!!! Good luck using whatever you decide to "fight" with.