Growing Sweet Potatoes and Sweet Potato Greens From Scratch
Growing Sweet Potatoes is such fun! Starting with growing your own slips to storing the roots. Sweet potatoes are a super healthy and versatile plant.
Equipment
- 1 container for rooting the sweet potato.
- 1 heat mat A heat mat is optional, but it helps speed the growth of slips.
Materials
- 1 or more Sweet Potatoes
Instructions
First Step: Growing slips
- There are two ways you can produce slips and root your sweet potato.
- Method one: involves submerging a third or so of the sweet potato in water to get it to root and sprout. You can use toothpicks to suspend the sweet potato partly in the jar if your jar is deep.
- Method two: Here you'll 'plant' the sweet potato partially buried in some potting soil. Some say to cut it in half first and pressing each half with the cut side down into the soil. I've tried both and it all worked.
- It should take about 4-6 weeks for your sweet potatoes to root and produce sprouts. Mine are already sprouting in storage, so they start growing slips pretty quickly. Wait till the slips are a few inches tall before proceeding.
- Once you have a few good sized slips, you can twist them off the potato and place them in a jar of water to root, or you can plant them into a 4" pot with damp potting soil. Rooting in water will save space and many gardeners just plant straight from the water dish to the garden when it's time. But if you find that you have to wait several weeks for the weather to improve before planting them, it helps to put them in pots. Just make a hole in the potting soil, then plant the sweet potato slip, burying the stem up to the first set of leaves.
- If your sweet potatoes start to rot while you're trying to grow slips, it's best to take off any slips that are big enough to handle and I just stick the tiny ones in a small bowl with some wet sand to keep them from drowning in a water bath. You can then compost the rotten sweet potato.
- Keep your sweet potato plants warm. At least 65 degrees or warmer is best for them. You can use a heat mat to help them grow slips faster.
Planting Your Sweet Potato Slips
- If you are planting your sweet potatoes into the garden, wait for several weeks after your last frost. Ideally you'll want the soil temperature to be 65℉ or higher.
- If you're living in the North with a short growing season, that might mean covering an area of soil, with black plastic mulch. Do that right around your last frost date to warm up the soil quicker, so you can plant into it 2-3 weeks later.
Planting In Pots
- If you have a greenhouse, this would be a great place to grow sweet potatoes in a cool climate. You can plant into the ground there or in large 20 gallon containers or grow bags. Consider using those cow mineral lick containers that you can often get for free or cheap from a farm. You can plant 4-5 slips in a 20 gallon container.
- You can also plant your sweet potatoes in a smaller pot for your balcony or indoors, once they outgrow your little 4" pots. You'll need about a 5 gallon bucket, pot, or grow bag per plant to get tubers. If you're just growing greens, you can plant two slips.
- Use a quality potting soil and amend with some compost and sand or vermiculite for better drainage. It's important that your soil drains well to avoid the sweet potatoes rotting.
- If planting in pots, be sure to keep the soil adequately watered, but let it dry out a bit before each watering. Lightly fertilize with plant food every 3 weeks or so. If you're growing them for the greens, plant food that is a little higher on the nitrogen works well. But for an overall good choice and rich mineral content try a very light application of liquid fish and kelp emulsion.
Planting Outdoors.
- Once the weather is stable and warm and the soil has warmed to at least 60, but better 65 degrees, you can plant your slips out into your garden.
Location
- Choose a sunny location. Sweet potatoes like it hot and love all day sun. I like to let them run around other plants who prefer cooler soil, where the sweet potatoes can shade their roots.
Soil Preparation
- Sweet potatoes like well draining soil with some compost. They are not very heavy feeders, so just some compost added to your garden bed before planting should go a long way to keep them happy. I didn't add anything else last year and mine put out super vigorous vines with huge roots come harvest time.
- In northern areas, place some black thermal plastic on your future sweet potato plot, after the last frost and about two weeks before planting. This can help warm the soil. You can leave it in place and just cut holes to plant your sweet potatoes into. The plastic will also keep this area weed free.
- If you are planting into a plastic mulch, mark your holes with an upright stick or flag, so when you go to water later in the season, and your bed is thickly covered with vines, you'll know where to put the water so it goes into the hole instead of running off the plastic.
Spacing
- Typical spacing is 12-18 inches apart. Be sure to give your sweet potatoes lots of room to sprawl. Their vines will grow to about 4 feet long, going in all directions.
- Just plant them slightly deeper than they were in their pot. You can just bury the whole stem under the first set of leaves. They'll put roots out along the stem too.
Seasonal Care
- While the potatoes are growing, it's a good idea to keep the vines from rooting in other places. When a potato vine roots in the soil it will try to produce tubers there and it will spend its energy on lots of small tubers all along its vine. Come harvest time, you'll find extra potatoes, but they all won't be very big.
- Mulching might help too, although I found mine rooting into the wood chips in my food forest. Placing a barrier, such as some brown paper bag pieces, between the vines and the soil can help. This will give you a smaller number of larger potatoes.
Pests And Diseases
- Sweet potatoes need little care throughout the season. I did not find mine much affected by the diseases or pests that decimated my other crops. But here are some of the problems that could befall your sweet potatoes.
- Common bugs are flea beetles, aphids, white flies, root knot nematodes and wireworms. They can be bothered by a number of other beetles too if they are common in your area.
- Here are some of the more common diseases to watch for: Streptomyces soil rot, southern blight, and circular spot.
- If you find an infestation of aphids, to apply some natural neem oil in a suspension mixed up of 2 tsp pure neem oil, 2 tsp castile soap and 1 quart of water.Neem oil can also help with white flies, leaf miners and many other pests. Neem oil also has antifungal properties. As with all applications, keep in mind that if it can kill bad bugs, it also has the capability to kill the good bugs. So watch out for ladybugs, bees and other beneficial critters that you want to keep safe, because they are your allies in the garden.
- As a prevention, maintaining soil health, crop rotation, companion planting, and proper irrigation practices go a long way towards keeping your sweet potatoes healthy.
Fertilizer
- I did not fertilize my sweet potatoes. I have a slightly raised bed (about 6 inches) that I filled with a homemade soil mix of a third each, compost, peat and pine bark. Underneath this is clay and gravel. It was sufficient to produce lots of greens and great big potato roots.
- Over-fertilizing will cause problems. Too much nitrogen will produce lots of greens and small roots, and it can actually produce unhealthy plants. So my advice is to hold back on the fertilizer and only use plant foods that are rich in minerals like liquid fish and kelp emulsion, greensand, compost tea, or comfrey tea. A mulch with comfrey leaves can also supply minerals while keeping the soil moist.
- Use a light solution of these natural nutrients and minerals every 3-4 weeks during the season, or if your sweet potato plants look undernourished. You can also add a little bit (just a few pinches) of Redmond real salt or unrefined sea salt to your water occasionally, which can help supply important trace minerals.
Watering
- Water your newly planted slips every day for the first week. And every other day for another week or longer if you're having a dry spell.
- After that, you'll want to deep water once or twice a week to maintain soil moisture. Mulching will help keep the moisture from evaporating while the plants are still small.
- Cut back on watering for the last 3 weeks before harvesting the tubers.
Harvesting Greens
- Throughout the season you can harvest the very nutritious sweet potato greens. Cut one or two of longest vines on each plant, leaving about a foot for regrowth. I waited till my vines were well established (about 45 days) and harvested just a small portion of each plant on a rotation.
- You can also prune off some fresh, tender side shoots or growing tips if they get in the way and cook them stem and all.
- I also pruned back a few of the vines that got too unruly. Just don't over-harvest, they do need their leaves to grow big roots, but they can suffer a few losses here and there without ill-effect. Don't harvest leaves from one plant for about a month after your last harvest.
- Use the younger leaves for cooking, that have a J-shaped stem. Leave the stem for eating if it's tender. Older stems get tough, just keep the leaves and discard the stems.
Companions For Your Sweet Potatoes
- Plant companions for sweet potatoes and your garden because they attract beneficial insects, they can deter pests above and below the ground, and they might confuse some pests because of their strong scent.Keep in mind the thick vining habit of sweet potatoes when planning your companion plants. Some that would be great companions in some ways, would just be overrun by the Sweet potato vines, but they could be planted near-by, such as Thyme and Sweet Alyssum.
Herb Companions
- Aromatic herbs are great throughout your garden to keep pests away or detract from the scent of certain plants to confuse pests. Try Dill, Oregano, Rosemary, Sage, Thyme. Summer Savory, Catnip and Basil.
Flower Companions
- Here are a few great flower companions for Sweet Potatoes: Marigolds, Yarrow, Daisies, Borage, Lemon Balm, Zinnias and Nasturtiums.
Vegetable companions:
- Sweet potatoes like to live with root crops such as beets, carrots, turnips, and parsnips. Parsnips can possibly compete with Sweet potato roots, because they are so long and deep. So plant parsnips in the vicinity, but not directly near your sweet potatoes
- Other helpful vegetable companions are Horseradish, pole beans, garlic, scallions, onions, spinach, corn, and mustard.
Dislikes:
- Avoid planting squash plants, melons and cucumbers near sweet potatoes. They will compete for space and might share pests.
- Avoid plants in the solanaceae family, which includes tomatoes, peppers, and eggplants. Apparently they can encourage diseases in each other. And don't plant the solanums where sweet potatoes grew last year.
Harvesting
- The best time to harvest sweet potatoes is before the first frost, or just after the first light frost. If you get hit with a frost that kills your sweet potato vines, be sure to harvest the potatoes right away to avoid them rotting in the ground. Try to pick a day after several dry days to avoid having too much soil stick to the potatoes.
When To Harvest The Tubers
- I prefer to harvest just before the frost for two reasons:
- It's a good idea to leave the potatoes out in the sun for a day or two to dry their skin before handling them too much, if the weather allows it. That's best done when night time temps stay above 50 to avoid cold damage.
- I like to take advantage of the still green sweet potato vines and collect as much of the tender shoots and leaves as possible for the freezer. The rest of the vine is great fodder for the goats.
Harvest The Sweet Potatoes
- Cut the vines but leave about a foot or so sticking out of the ground that serve as markers. If you grow them all over the place, like I did, it also helps to place little survey flags wherever your plants are growing, or you'll be hard pressed to find them all.
- Next, try digging with your hands first to get all the potatoes you can. If your sweet potato vines were rooting in other places, away from the main hole, check there too. They like to make potatoes anywhere they root.
- If there are still sweet potatoes that you can't get out by digging with your hands, grab a garden fork and carefully loosen the soil around the potatoes and lift them out of the ground.
- Don't clean them right after harvest. Leave the potatoes on the ground for a day or two if it's warm and dry enough, to dry and harden their skin a little. After that, you can try to gently wipe off the worst of the stuck on soil with a soft cloth, such as a terry washcloth. Always take care not to damage the skin.
- Now gently gather up the potatoes in a basket or box and take them to a place to cure.
Curing
- This step is necessary. You'll be curing your sweet potatoes for 7-14 days in a warm location around 85℉ with 85% humidity. Keep them spread out on a table or a rack. After that they need to cure for another month at 55-60℉. This process will develop the sugars in the sweet potatoes. They will not taste sweet when you first harvest them.
Storing
- Now store the sweet potatoes at above 50 degrees and up to about 70 degrees in a breathable container, such as a burlap sack, a basket or a wooden slatted crate. If the temperature falls below 50 they can get cold damage and rot. So do not store them in the refrigerator.