Answer: Did each piece have an eye? Each seed potato should be about the size of an egg and have at least one eye (sprout). If they need to be cut into the proper size, be sure to let the pieces dry for a day or so. If the soil is cold, sometimes the seed potato will rot before it can sprout.
It's not too late to plant them. (I planted mine the second week of June last year--and still got a good yield. I used lots and lots of compost in the planting bed, though. That might have helped!)
Tubers form above the seed potato, not below it, so plants must be hilled to get good yields. With a rake, draw soil up around the plant when it is 6-8 inches tall. Just let the top leaves peek through. You can also use hay or leaf mulch, adding more as it grows. Remember to water them regularly and DO NOT USE FRESH MANURE...it encourages scab.
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