Sweet potatoes are typically grown from slips, which are sprouts that have developed their own roots. You can grow your own slips at home using a whole potato OR purchase slips from a garden center or online retailer. If you can’t plant your sweet potato slips as soon as you purchase or receive them, simply place slips in a jar of water or pot them up in some garden soil until you can get them planted.
Sweet potatoes are extremely frost sensitive- plant slips 3-4 weeks after your last spring frost date and after the soil has warmed to a minimum of 60F. Sweet potatoes prefer well-drained, sandy loam soil. If you have heavy, clay or slow draining soil, forming raised planting rows or beds and amending with well-aged compost is a good option for growing sweet potatoes. Consider laying down black plastic or fabric weed barrier prior to planting, as this helps warm the soil, suppresses weeds and keeps vines from rooting in the soil, which will divert energy from tuber formation (and in general will make your life easier).
Space sweet potato slips 12-18 inches apart, in rows 3-4 feet apart. Cut a hole in your plastic or fabric for each slip. To plant slips, dig a hole deep enough to accommodate the root portion of the slip and firm soil around the base. Give each newly planted slip a generous drink of water and keep young plants well-watered. Once the plants are established, they are tolerant of dry soil, but 1” of water per week is ideal. Avoid watering during the several weeks prior to harvest if possible. This keeps mature tubers from splitting.
Sweet potatoes are not heavy feeders, and if you have nutrient dense soil or work in compost before planting, supplemental feeding may not be necessary. If your soil is nutrient depleted, side dress your potatoes 3-4 weeks after transplanting. Avoid nitrogen heavy fertilizers, as this will lead to a lot of lush vine & foliage growth, but small, stunted tubers.
Sweet potatoes are typically ready to harvest when the leaves have started to turn yellow, or about 3-4 months after planting. In Northern areas, they can be left in the ground until the first fall frost- but you’ll want to get them out of the ground as soon as possible after that point. Cut vines back and peel back your weed barrier. Start digging about 8-10 inches from where the main stem comes up out of the ground. Gently dig or fork around the area to remove tubers from the soil, avoiding knicking or piercing tubers while digging if possible.
For long term storage and to obtain full flavor, you’ll want to cure your sweet potatoes. Let your freshly harvested potatoes dry in the sun, then move to a curing room. The ideal environment is 85-90 degrees and 85% humidity. Cure potatoes for 7-10 days, then move to a root cellar or basement, where tubers can be kept at 55-60 degrees. If you plan to eat your potatoes within a month or 2 you can simply air dry them at 75- 80 degrees, then put into storage.
Learn how to plant sweet potatoes, how to grow sweet potatoes, how to harvest sweet potatoes, how to cure sweet potatoes and how to store sweet potatoes.
