Potatoes are a tuber vegetable that thrive during the cooler weeks of the growing season. Potatoes grow best at soil temperatures of 60 to 70 degrees Fahrenheit. Soils over 80 degrees are not conducive to tuber formation, so gardeners must plant potatoes as early as possible in the spring to harvest before the soil warms. Potatoes grow most successfully in the cooler regions, although gardeners in warmer zones may harvest potatoes in cooler months of the year.
Lay down a 2-inch layer of mulch around the growing potatoes to prevent weeds, cool the soil and keep the soil moist.
Add loose soil around the base of the potato plants as they grow to keep the tubers from turning green during the growing process. Every few weeks, add more loose soil around the potato plants to ensure that the tubers stay well under the ground as they grow. By the time the potatoes are ready to harvest, you will have added as much as 6 inches of soil around the growing potato plants.
Keep the potatoes adequately watered throughout the growing season. Adequate water is important, especially when the potato plants are blooming. Provide water in the morning hours to allow the leaves to dry before nightfall. When the potato leaves turn yellow, stop watering because harvest is only one or two weeks away.
Harvest potatoes any time after the potato vines die back. This is generally a few weeks after the potato plants bloom. Harvesting soon after the vines die will yield small potatoes, and waiting longer will yield larger potatoes. Harvest potatoes any time between the time when the vines die and the end of the growing season.
Dig carefully to remove the tubers from the soil, placing your shovel into the soil approximately 1 foot outside of the planting area. Gently use the shovel or garden fork to find the potatoes growing between 4 and 6 inches under the soil. Allow the potatoes to dry for at least 2 days without washing them so that the skins will mature.
Store potatoes in a dark location at a temperature of approximately 40 degrees Fahrenheit. Potatoes stored properly will keep over the entire winter. Check the potatoes every week, and remove any that are spoiling.