Growing Sweet Potatoes
While growing sweet potatoes may be identified with the southern regions of the United States or South America, sweet potatoes can be cultivated in just about any garden, and even in containers. This is a tuberous root plant, and it is the root that we eat.
The sweet potato is a perennial that is also a vining plant. Interestingly enough, the sweet potatoes that we eat are related to morning glories also officially known as Ipomoea tricolor. The sweet potato vining plant is grown both as an edible plant and as an ornamental plant, both are Ipomoea batatas.
In the United States, even though they are two completely different vegetables, the names sweet potato and yam are used interchangeably. They also have no relation to a regular potato. While the most common and well-known sweet potato has orange inner flesh, sweet potatoes come in several colors such as white, purple or yellow.
They are also very easy to grow. As a vining plant, they will root wherever they come into contact with the ground. This means a couple of plants can produce a good number of sweet potatoes. Take heart if you happen to have a small vegetable garden plot and wish to grow sweet potatoes because there are bush varieties.
Some well-known and popular varieties include:
- Patriot – this is a favorite choice for organic gardeners as it is very pest-resistant
- Beauregard – This is a very popular commercial sweet potato. It matures in 100 days.
- Georgia Jet – A variety that matures quickly in 90 days.
- Bush Porto Rico – A variety that has a compact vine that will mature in about 110 days. It gives generous yields and is a terrific choice for smaller garden plots.
How to Plant Sweet Potatoes
Sweet potatoes will need a sunny location in soil that is well-draining. Originally a tropical plant, they need for the soil to have warmed up completely before being planted. Sweet potatoes cannot be planted outside until the soil temperature has reached at least sixty degrees Fahrenheit. It is a good rule that the soil temperature should fall between 60 and 85° F and the air temperature between 65 and 95° F.
When preparing your soil bed, add compost to the soil before you begin planting or you can use organic fertilizer in liquid form as an alternative. These vegetables are planted using slips that you can purchase. Slips are small pieces of tuber with roots. These can be purchased from a reputable seed vendor as you will want to make sure you plant healthy roots.
Plant your sweet potato slips in rows with the rows placed three to four feet apart within your garden. When planting sweet potatoes, they should be planted with twelve to eighteen inches of space between each slip because the vines will spread out and then fill with tubers so they will need the room to expand.
If you garden in an area with a cooler climate, you can speed up the warming of your soil by spreading black plastic over the area where you intend to grow your sweet potatoes. However, if your garden plot has dense soil or if it is rocky, you may want to create a raised soil bed with rich and sandy potting soil. In this case, plant them in raised rows about eight inches in height. This choice for planting them will also enable the soil to warm up quicker and will also ensure good draining. Plants should be kept moist, especially if you are in an area subject to dry spells.
Caring for Your Sweet Potato Plants
During the growth period, consider the following aspects to guarantee an abundant successful harvest:
- These tubers should be planted in an area that enjoys full sunlight to partial shade. They prefer direct full sunlight, but if you live in a hot, drier zone, partial shade in the afternoon is recommended.
- Soil Bed. Sweet potatoes flourish in well-draining soil that is rich in organic matter. Sandy soil is more appropriate than a dense clay-like soil bed.
- How Much Water? Once your tuber slips have established themselves in the soil, they can grow with less water. The soil bed should be moist throughout and it is sufficient to water once a week with approximately an inch of water.
- Should I fertilize? These plants do not require a lot, just balanced nutrition. Proper soil bed preparation should be sufficient. If you over-fertilize, the plants will produce a good deal of foliage and not necessarily tubers.
When to Plant Sweet Potatoes
This slow-growing tuber is planted in the spring because it requires a good three or four months of warm weather in order to develop into a full-sized vegetable.
When to Harvest Sweet Potatoes
Anywhere from three to four months after planting your sweet potatoes should be ready for harvesting. The final three to four weeks before you harvest, you may want to avoid watering altogether. This will prevent any mature tubers from splitting open. If you like the leaves as greens, they can be consumed throughout the growing season but always leave some leaves for plant growth.
Once the leaves begin to yellow, you can harvest. Do not leave them in the ground if the tops die, because the plant will start to rot shortly afterward. Dig them up gently as tubers have delicate skins that are easily damaged during harvesting. Should a frost affect the exposed leaves, the tubers will probably be alright.
If you live in a cold climate with longer winters, you can store your tubers throughout the winter to plant the following spring. Tubers should be dug up before the first frost of the autumn. They should be stored in a dry material such as peat or vermiculite. They should be stored in a dry, cool dark place, ideally a root cellar or even a basement. Come spring, the tubers will begin sprouting. At this point divide them into pieces. Each piece should have at least one eye. They can be planted when there is no longer a risk of frost and the ground temperature should have reached at least 60°F.
Should you live in a warmer climate with a short winter, you can clip pieces of the vine, creating vine cuttings. Clippings should come from the tips of the vines and be about six inches in length. Clip before the first frost arrives. Put your cuttings in water. When they form roots, you can plant them in soil pots and put them in a sunny place until it’s time to transfer them into your garden.
If you want to use a full-grown mature sweet potato to begin your crop, cut the potato lengthwise in half and place the halves in damp potting soil. Cover the halves with soil. Now keep them warm and moist. After several days, roots should develop. Shortly after leaves will appear. When they grow four to eight inches in height, you can transplant them into your garden. This should happen in about six weeks.
Pests and Diseases
Common pests for sweet potatoes include:
- Root-knot nematodes
If you rotate your crops annually, it will help avoid diseases and some pests. The planting of disease-resistant varieties will also help.
How to Store Sweet Potatoes
In order to maintain your harvest, avoid placing sweet potatoes in the refrigerator. Place the potatoes in a cool, dry container that is well-ventilated. Storage in a basement or root cellar is recommended. Sweet potatoes normally store well for up to two weeks.