I planted three varieties of potatoes on April 1. German Butterball, Kennebec, and Desiree. A few weeks ago, the plants started yellowing a bit and getting crispy edges. I feared late blight, but discovered it was actually potato leafhopper, which I sprayed for, and they got new, darker green growth. At this point, although the vines are long and lying flat, they’re as green as ever and show no signs of dying back.
I dug some delicious new potatoes around July 10, but at that point only the Desirees had sized up well, many were as large as “grocery store size”. The Kennebec and German Butterballs were all golf-ball sized at best at the time.
I wonder if I should just let them go a bit, or cut the vines down, give them a couple weeks to cure their skins, and dig them. Our soil temps are 75 – 80F even at tuber depth, so I don’t know if I’ll get much more tuber growth due to the hot soil, unless the four days of rain we had cooled it off a bit.