Below is some information from ATTRA, with organic and physical ways to fight this beetle. One advantage to using row covers is that the plants don't need pollination. If you could plant this year's crop as far away from previous planting sites, and covered the plantings immediately, you might limit infestations. Diatomaceous Earth (DE) works on beetles, but it has to be dry to do it. There is a theory that if you plant flax among your potatoes, it will repel the beetle. Sue Here is a link that might be useful: Controlling Colorado potato beetle

Was just going to ask what you mean by wide-row planting. :) I assumed in my first post that you were talking about exactly what you now describe - Wide-row gardening, a defined method that is very popular with those of us with large in-ground beds. It is a BIG acreage garden method of growing not normally associated with raised beds or small backyard gardens although I'm sure some try it. Normally that means 4' wide slightly raised mounds of soil 50-100' long (depending on the crop) and the plants are stagger or scatter planted in a wide band the entire width of the wide-row. Planted all over that bed, not in rows - if you follow me. Double row planting is something else entirely. So as I said above, potatoes are not usually considered a wide-row crop because of the difficulty with hilling and harvesting. I'm not saying it can't be done. You can always heavily mulch the whole 4' wide row. Or you could plant 2 defined rows along the outside edges in a 4' wide-row and hill both from the center but that wouldn't be wide-row gardening. Or you could trench them in and don't worry about hilling (depending on the variety) but then you are also losing the advantages of wide-row gardening Hope this clarifies. Dave Here is a link that might be useful: Wide row gardening images

Some swear they must be E to W. Just as many others swear by N to S. Truth is it doesn't matter and is your choice so since it is flat, go with whatever works best for you in your plot. ;) Dave

i used them for a couple of years and no longer do. they worked pretty well, but in the end i felt they were more trouble than they were worth to me, and i did get some beetle damage. possibly they would work better for a more attentive gardener. i had to lift them up in order to hill the potatoes at least twice. maybe beetles got in that way. or maybe they got in where the cover was imperfectly meeting the soil line. maybe there's an easy way to keep the row cover in place along the bottom, but i didn't find one. i used plastic hoops made into arcs about 2 1/2' or 3' tall and found that the plants started bulging through when they got tall, poking holes in the covers. after a few years of this, i decided to forgo them and try to hand pick the beetles. i usually plant about 40' of row, or 40 plants. it would take 2 to 3 hours once or twice a season to check every leaf bottom (sounds much worse than it is) and squash all the eggs. i was amazed at how successful that is. and you get to see the plants, rather than the row covers. last year i did 3 things i'd never done before, and shockingly, i had NO beetles at all!! i don't know which factor it was, but this is what i did: 1) i planted the seed potatoes on june 15, (2 months later than usual) 2) i mulched the beds with straw (instead of hilling with soil) and mulched the surrounding paths with straw too. i read that they don't like straw. 3) i planted 4 horseradish plants, one at each corner of the patch. maybe by planting them late i missed the beetles' reproductive cycle. i don't know, but that's my best guess. that's my experience. i'm sure some people have had better luck with the row covers. good luck!