Potatoes are easy to grow, but instead of planting from seeds, they are grown from portions of the root structure, called seed potatoes. Seed potatoes are tubers that you can use to grow new potatoes that will be genetically identical to the parent potato. Potatoes grow more expediently by this kind of vegetative propagation, and for most home gardeners the process is easier than growing from seeds. Typically it can take about 60 to 90 days for potatoes to grow after planting. When to Plant Seed Potatoesplant seed potatoes in the early spring so you can harvest them by mid-summer.Potatoes do best in full sun. They can be planted in the early spring two to four weeks prior to the expected last frost date in your area.Seed potatoes planted in soil that is too cold or soggy may rot.1 Generally, potatoes will not grow until the soil temperature has reached at least 45 degrees Fahrenheit. You can plant a second crop as late as June 15th depending on location and harvest the potatoes as late as possible. Potato plants will tolerate a light frost, but protect plants from freezes with row covers, or harvest them before a freeze arrives.Chit the Potatoes (Optional)Although potatoes will sprout in the dark, you will get long, pale shoots that easily break. Instead, place them in a cool spot with bright light for 2 to 4 weeks. This way, the sprouts will grow stocky, sturdy, and dark green. This process is also called greening. You can place your seed potatoes upright in an egg carton or box, on a tray, or screen with the majority of buds ("eyes") facing up. Do not pile them atop one another. You can start this process one month before your outdoor planting date.