Most of my tubers are still in saran wrap. I don't plant till the end of May and I don't have enough sunny windows to accommodate all the plants. If I start them too early, I end up with tall, spindly plants before time to put them into the garden. My new arrivals are put into zip lock bags of potting mix. The mix is just to keep the tubers from drying out too much, so I don't add water. It seems a little dampness kickstarts them into too much growth before I'm ready. I'll get serious with the starting and potting toward the end of this month. Some of the tubers are anxious and have sprouts that have poked their way through 2 or 3 layers of saran .
