Timing The Potato Planting
Potatoes can be planted very early in the season -- almost as soon as the frost is out of the ground and you're able to work the soil. In the North, you can plant your first crop of early maturing potatoes in April, usually six to eight weeks before the last frost.
For other gardeners, especially those in the South, the planting dates are quite different. Down South, planting times range from September to February. Where winters are relatively mild, you can plant a fall crop in September. In central Florida, gardeners plant potatoes in January; and in Georgia they plant in February.
Don't be afraid to start early with potatoes in the North. They can survive several inches of snow and fairly cold temperatures. The soil, not the calendar, will tell you when it's time to plant. The soil should not be so wet that it sticks together and is hard to work. Let it dry out a bit first. Like other seeds, potato seed pieces will rot if planted in ground that's too wet.
Sprouting Tip for Earlier Harvests
If you look forward to early potatoes, you can hurry the harvest along by forcing the eyes to sprout a few weeks before planting. By planting potato pieces that have already sprouted, you shorten the time it takes a plant to come out of the ground and develop the leaves that will eventually provide the energy to be stored in the potatoes.
To sprout seed potatoes two to three weeks before planting, spread them out in a single layer on an enclosed porch or in a warm room where they'll get some sun and where the temperature will stay near 60oF or warmer. The potatoes will develop short green sprouts, rather than the long white sprouts they produce in the dark.
Because the potatoes turn green, this sprouting process is often called "greening". Green potatoes aren't good to eat, but when you plant them the crop will be fine. When planting time comes, cut the potatoes as usual and plant the seed pieces without breaking the tiny sprouts.
Photo by Suzanne DeJohn/National Gardening Association