Hie thee down to a good garden center or nursery—or library—and look for a copy of the Ortho Garden Pest Book. They will usually have one chained to a podium for the public to use. It is a huge book, but very easy to use, as it is written for average homeowners, rather than professionals.
Naturally, it is geared toward pushing Ortho products, but sometimes it gives other alternatives; but, in any case, it will identify what’s bugging your plants, and give a decent description of what you’re dealing with.
Never mind their recommended chem solutions; just use it to find your problem pest, to use as a starting point for further research to find what you need to do to combat the specific problem..
Also, you said you ‘planted eyes’. How much potato was attached, or was it (common beginner mistake) almost just the eyes? Were the pieces allowed to callous over before planting? Were the potatoes used sound & healthy looking?
Usually, something like what you’re seeing is just a cleanup crew doing its job; not the killer itself which is almost always rot. Soil too cold; soil too wet; seed planted immediately, not cured after cutting; infected seed, etc.
Thank you for that info. I have planted potatoes before in a different location several years ago so I went from memory (maybe not a good idea) for how I prepped them before. I used store bought organic potatoes that were just starting to sprout. I cut pieces of potato that were about 1” square and had at lease 1 eye that was just sprouting. I left them up on the counter for 2 days to “cure” and then planted them about 2” deep. We’re in central Florida, so definitely not too cold and the soil is pretty well drained.
Good meaningful questions which get to the 'heart of the matter'.
All cuts on the potato should be exposed to sun to callous over (scab on the cuts).
I like to include at least a 2 by 2 inch piece of the original potato along with the 'eye', and thuroughly calloused by exposure to sunlight.
Potatos are a member of the solanacious family (solar = sun light) as are peppers , tomato , eggplant , etc.
Crop rotation should be practiced so as not to plant solancious plants where other had been planted in the last 3 - 4 years; otherwise there may be pest/disease in the soil.