How to Grow Potatoes from Potatoes

Growing Potatoes in Your Yard

Choose a spot in your yard with lots of sun. Potatoes grow best with 8 hours of sunlight a day, but they don’t do well with too much heat. Pick a spot in your garden where the plants will be exposed to sunlight but not baking in the heat. They prefer summer temperatures of roughly 70 °F (21 °C), but can handle slightly hotter temps, as long as they’re not exposed to direct sunlight for more than 6-8 hours a day. Plant in late spring for ideal conditions. Expert gardeners recommend planting potatoes around the time of last expected frost, but that time can vary based on where you live.

Buy seed potatoes from a garden supply store. The best way to grow potatoes is from potatoes, but not just any potato will do: they have to be specially-grown seed potatoes from a garden supply store. Regular potatoes from a grocery store are often treated with pesticides which can spread disease through your whole crop, so either order your seeding potatoes from a catalog or hit the garden store. Seed potatoes come in every variation—russet, Yukon, fingerling, you name it. Your garden supply store will have options for you to choose from, and they can order you any type of potato they don’t already have in the store.

Allow sprouts to grow for 1 week before planting. Unlike most grocery store potatoes, seed potatoes grow little protuberances called sprouts. These sprouts, once planted, form the buds of new potato plants—they are essential to the growing process! Place your seed potatoes in any warm, dry spot (a bowl on your kitchen counter where the sun shines will do) and leave them for a week. One week is ample time for your sprouts to grow between ⁄4 inch (0.64 cm) and ⁄2 inch (1.3 cm) in length. That means they’re almost ready to be planted.

Cut the potatoes into 2 in (5.1 cm) sections. Tiny potatoes are fine to be planted whole, but any spud larger than a golf ball should be cut into chunks about 2 inches (5.1 cm) wide, each with at least two sprouts. Usually just cutting the potatoes in half “hamburger-style” will do. Return the cut potatoes to the warm spot where they’ve been sitting for the past week, and leave them an additional 2-3 days before planting.

Prep the plant site with fertilizer. Using a garden fork, rake compost into your chosen plant-site. Potatoes prefer loose, loamy soil, so work out any clumps until the dirt is airy and breathable. Make sure your fertilizer is covered by at least 2 inches of soil or it could damage your potato roots. If you don’t have compost, buy a balanced commercial fertilizer, superphosphate, or bonemeal, all available at the garden supply store.

Plant the potatoes in holes 12 inches (30 cm) apart. Place your halved potatoes cut-side down in 4 in (10 cm)-deep holes with the eye, or sprout, pointing up toward the sun. Cover with soil and water well. You should generally provide your potatoes with 1–2 inches (2.5–5.1 cm) of water per week, including rainfall. They prefer their soil moist, but not waterlogged.

Hill the potatoes after five weeks. To “hill” your potatoes, pile soil up around the stems to create a 1 foot (0.30 m) incline on either side. This will force new potatoes to grow above previously-planted ones. You can cover the entire plant with soil, or choose to leave the leaves exposed (this may be helpful later, as their changing color can signal the potatoes’ growth). Continue hilling about once a week: it will protect baby potatoes from being exposed to direct sunlight.

Harvest your potatoes after 70-100 days. Somewhere around five months after their plant-date, your potatoes will begin to show signs that they’ve matured. The leaves will turn yellow and the foliage will die back, meaning it’s almost time to harvest them. Leave them in the soil an additional 2-3 weeks, then dig them up with a pitchfork and gather them with your hands. Many species of potatoes will grow into tubers large enough to eat after 10 weeks, but leaving them in the ground longer will yield the largest crop.

Planting Potatoes in a Pot

Fill 1/3 of a large, deep pot with potting soil. The bigger the pot, the better (potatoes need lots of room to grow), but at a minimum it should be 10 gallons (38 L) for 4-6 seed potatoes. If you plan to grow more than 6 seed potatoes, go for a barrel-sized pot. Your pot will also need to contain a sizable drainage hole. Black reusable plastic pots from the garden store work well for growing potatoes, as the black color holds in warmth and the bottoms have built-in drainage.

Plant seed potatoes 6 inches (15 cm) apart with sprouts face up. Your potatoes should not be touching each other or the edge of the pot or their growth will be stunted. Once planted, cover them with 6 inches (15 cm) of potting soil. Water until the liquid begins to drain from the bottom. Leave the pot in a sunny, temperate spot on your front or back deck, where it will be exposed to 6-8 hours of sunlight per day. Don’t overcrowd the pot: 6 inches (15 cm) is the minimum amount of space in which your potato can still grow.

Water your potatoes whenever the top 2 inches (5.1 cm) of soil become dry. The dryness of the soil will depend on the weather where you live, so test if it’s time to water by sticking one finger into the top of the soil. If it feels dry, it’s time to water again. Keep going until water begins to drain from the bottom of the pot. If you live in a hotter climate, your soil will get drier quicker and will need to be watered more often. Check twice a day.

Add potting soil as your potato sprouts shoot out of the soil. Only about 1 inch of the sprout should be exposed at any point in the growing process, so continue to add soil periodically. Mix your soil with fertilizer (a 5-10-10 commercial mixture from the garden store will do) for healthy, fast-growing plants.

Harvest your potatoes when their leaves turn yellow. After 18-20 weeks your potted potatoes will reach maturity. Dig them out of the pot by hand or dump it out and root through the soil to harvest your tubers. Check the skin of each potato for white, mushy spots—these could signify fungus, in which case the potatoes are not safe to eat. They should be uniform in color with tight, firm skins.