Tag Archives: growing sweet potatoes

Sweet Potatoes From Order to Plate

Sweet potatoes are really underutilized in backyard gardens. They’re so easy to grow, nutritious, and tasty. They’re often overlooked and many believe that the store-bought and homegrown versions are virtually indistinguishable but that couldn’t be farther from the truth. Store-bought sweet potatoes tend to be of a few hardy, orange varieties. While they’re absolutely still delicious there’s so much more variety to be had if you grow your own.

Just like other crops there’s sweet potatoes that are better suited to different growing conditions and cooking methods. The classic orange Beauregard is an excellent baker while the white fleshed O’Henry is one of our favorites for mashed potatoes. The Bunch Porto Rico has compact vines better for small gardens while the All Purple is especially hardy.

There are also dry and moist varieties. Dry varieties tend to be starchier and are more like regular potatoes. Some people consider them to be more versatile. Moist varieties are often sweeter and usually are the ones you find at the grocery store.

Choosing a variety can be tough so it may be wise to try a mix. Southern Exposure has two mixed packages available.

Bed Preparation

Sweet potatoes thrive in loose, well drained soil. If you have heavy soils it’s a good idea to work in a lot of compost and maybe even broad fork your garden bed before planting. To help with drainage you can grow sweet potatoes in raised beds, ridges, or hills.

Sweet potatoes also prefer warm temperatures and a relatively long season. Using black plastic mulch to help heat up the soil may be a good idea for those in cooler climates.

Surprisingly sweet potatoes don’t require especially fertile soil. In fact using chemical fertilizers often leads to tiny potatoes and huge vines. Simply adding some compost before planting is more suitable.

Planting

Unlike regular potatoes, sweet potatoes cannot be planted using seed potatoes. You need to use slips. Slips are the eyes on sweet potatoes. These are grown and then broken off to be replanted.

Note: for information on saving sweet potatoes and growing slips for next year check out our growing guide.

Slips should not be planted until 3-4 weeks after your last frost date. They’re very susceptible to frost. They should be planted 2-3 inches deep with their leaves above the soil. The slips you receive may or may not have grown roots already but they’re fine to plant either way.

Sweet potatoes have large sprawling vines and require quite a bit of space. You can plant sweet potato slips 10-18 inches apart in rows 3 feet apart. Water them the evening after you plant them and be sure to keep them moist for the next few days as they get established.

Care

Sweet potatoes should be mulched soon after planting. If you’re in a warm area where black plastic isn’t required straw or old leaves can be used. This will help keep the soil moist and block out weeds. Until they’re large it’s a good idea to keep them well mulched or weeded occasionally to keep weeds from overtaking them.

While sweet potatoes don’t like to be soaked (too much water can cause rotting) they do better with consistent waterings especially in dry areas. Too little water can lead to splitting and poor yields.

Pests & Diseases

Sweet potatoes can be affected by a number of pests like sweet potato weevils and diseases. The best way to combat them is purchasing healthy disease free slips, using simple crop rotation, and through maintaining healthy soils.

They’re also a favorite of deer so make sure you fence them off or cover them with netting.

Harvest & Curing

Aside from the potato itself the sweet potato shoots can also be harvested for cooking greens throughout the season. Just ensure you don’t take too much and kill the plant. 

Choose a dry, sunny day to harvest your potatoes. It will make both harvesting and curing much easier. Potatoes can be dug whenever they’ve reached an ideal size. It is best to harvest them all before the temperature dips below 55°F. Any lower temperatures can harm their storage capability.

Use a garden fork to lift them from the soil before collecting them by hand. Be careful and try to avoid nicking or damaging the potatoes. You may have to search a bit as they can grow up to 1 ft away from the plant itself. Sweet potatoes should be dried before any excess dirt is shaken off. Do not wash them, they don’t store well when washed.

For the first 7-10 days they should be kept at about 85°F and 90% humidity to cure. Then they can be stored at about 55°F in a dry, dark, well-ventilated area. Colder temperatures will affect their flavor so don’t refrigerate them until they’ve been cooked.

Any sweet potatoes with nicks or bruises will not keep well and should be used up first. You should regularly check you potatoes in storage and remove any bad ones as needed so they don’t spoil the whole crop. Properly cured sweet potatoes stored under the right conditions will keep 5-12 months.

Summertime Sweet Potato Ideas

If you still have have sweet potatoes in storage from last years garden (or are now craving them) there’s a couple simple ways to cook them even in the summer heat. Unlike in the autumn where I don’t mind baking them and heating up the house, in the spring and summer I typically cook sweet potatoes outside.

The simplest method is to clean them, poke a few holes in them, and wrap them whole in tinfoil before popping them onto a grill or into the coals of campfire. Alternatively they can be thinly sliced and wrapped in tinfoil packages with slices of onions, other veggies, and seasonings. All the ingredients should be drizzled in oil oil and the edges of the foil should be rolled or folded tightly to avoid leaking. Then they can be cooked just like the whole potatoes they’ll just cook much quicker.

Sweet potatoes truly are a wonderful crop. They’re high in vitamins and their storage ability makes them great for people looking to lessen their dependence on a global food system. It’s not too late to order slips! Try one of our productive varieties in your garden this summer.

What’s your favorite sweet potato variety?

How to Sprout Sweet Potatoes for Slips — Green Shoots for Planting

Sprouting sweet potatoes to make slips (the green shoots from a mature sweet potato that are used for planting) is one of our favorite spring activities. If you haven’t selected and stored roots from last year’s harvest for this purpose, you’ll need to order sweet potato slips (or if you want to add a new variety to your harvest).

Read on to learn how Sean at Living Energy Farm grows his sweet potato slips in early spring. You’ll also learn how to select seed sweet potatoes and store them through the winter to grow your own slips next year.

How to Grow Sweet Potatoes: Sprouting Your Own Slips

by Sean Thomas

Growing sweet potatoes is a year-round adventure, with lots of activities to keep you busy even in the winter and spring. They’re also an easy vegetable to seed-save and grow again each year. It’s fairly simple, with a bit of knowledge and work, to produce your own sweet potato slips (sweet potato vines) for transplanting. And if you sprout your own roots, you’ll get 2-3 times more slips per sweet potato. That’s a lot of extra taters.

Selecting Roots for Growing Sweet Potato Slips

The first thing you need to know is which roots to put aside for sprouting. Luckily, the best sweet potatoes for eating aren’t the best for producing slips. All those big impressive sweet potatoes you dug up, you can eat those. It’s the smaller ones you want to save because they’ll be the best for sprouting.

The ideal size for a slip producing sweet potato is about two inches in diameter. In the photo to the right there are some Violettas, a purple sweet potato with white flesh grown at Living Energy Farm. The large eating ones are on the left, and the smaller ones for slip production on the right. We select our seed stock right in the field after harvest, but you can pick them out now from the roots you’ve been storing. In my kitchen, I find smaller ones left this time of year anyway, because it’s hard not to eat all those big taters first.

A Quick Word about Storing Sweet Potatoes Over the Winter

Winter storage is the same for eating sweet potatoes and slip-producers. It’s best to keep them inside somewhere, in a dark place, like in boxes or paper bags in a closet, and then covered with a blanket to keep out any sunlight. The ideal storing temperature is between 55-60 degrees. If the temperature rises too high they can sprout early, and if it falls below 50 for an extended period of time they’ll harden up and become pretty much useless. It’s great to store your eating sweet potatoes for as long as possible, but storage is even more important if you want to grow sweet potato slips, because those roots will have to make it to March.

We store our organic sweet potatoes overwinter with the dirt still on the skins (we gently brush off any excess dirt) because this keeps the skins intact and the roots healthy and ready to sprout in the spring.

Sprouting Sweet Potatoes

So you’ve stored your sweet potatoes over the winter and picked out your seed stock. Now it’s time to sprout them. First you want to figure out how many slips you’ll need. Most commercial producers figure on 1000 slips per bushel, but if you’re doing this at home, a good rule of thumb is 10-15 slips for every root around 1-2 inches in diameter (If the roots are eating size figure on about 6 slips per root).

It will take about 4 weeks to sprout your sweet potatoes. I put mine in a dark closet the first week of March, the roots in paper bags and boxes for good air ventilation, with a small heater and humidifier on the floor of the closet. The ideal temperature for sprouting is 75-85 degrees with 90% humidity. I keep the door closed to protect them from any sunlight and I check the temperature and refill the humidifier daily.

After a couple weeks, you should start to see some sprouts form on the end of the roots. When most of your taters have sprouts about ¼ inch long, they’re ready. If sprouts start getting longer than that before you are ready to plant them, just turn down the heat a bit. If after a couple weeks you don’t see any sprouts, you’ll probably need to turn up the heat.

There are sixteen varieties of sweet potatoes in our sprouting closet: orange, white, gold, and purple sweet potatoes, all grown at Living Energy Farm in Virginia. They’ve been sprouting for a few days now. By the end of March the weather will warm up (hopefully) and the sweet potatoes will be all sprouted. Then it’ll be time to bed down the roots, but that’ll be left for another post.

Good luck sprouting!