Tire Grown Sweet Potatoes
Sweet Potatoes in the Round
My favorite way of planting sweet potatoes is to plant them in tires around the edges of the garden. I do not believe that an easier way to grow sweet potatoes exists. Planted in tires two high, sweet potatoes grow like crazy. The heat that the tires produce along with plenty of water gives this plant the tropical conditions in which it thrives. By growing sweet potatoes in tires, they can be grown even further north than they could otherwise.
Although not related to the white potato, sweet potatoes are a tuber and is grown and eaten as though it were a warm weather potato. Each tuber contains large amounts of vitamins A and C as well as protein, calcium, magnesium, iron and carotene. They can be eaten raw, boiled, fried or baked as well as in soups, casserole, desserts, breads, and in stir-fries and is a tradition at Thanksgiving.
Concerns About Toxns
Some people worry about using tires to grow sweet potatoes because they are afraid that the gas coming off the tires can be harmful. From my own research, I believe the gas and chemicals leaching from the heated rubber is a minimal problem at worst.
From my research, I believe that planting in tires over the short term is okay. Tires tend to get hotter than most plants like, however, that is not a problem with sweet potatoes. As long as sweet potatoes keep well watered, and the soil in the tires changed out every year, you should have not problems. However, over the long term, the tire's rubber will slowly release zinc, carcinogenic PAHs (polycyclic aromatic hydrocarbons along with other toxic compounds into the soil. The process required to break down tires takes many years thereby making the hazards from a single season of sweet potato growing minimal.
At a Glance: Planting Sweet Potatoes
Sweet Potatoes start from slips, not seeds. Start your own slips by sprouting sweet potatoes in a sunny window. Plant slips outdoors after all danger of frost has passed.
Planting Depth:six inches deep
Plant Distance Apart: One foot apart
Time until Harvest:90-170 days
Harvest sweet potatoes before first frost in the autumn.
Sweet Potatoes are not grown from seed, nor are they grown from the potato like regular potatoes. Instead, sweet potatoes are grown from slips. To grow slips, save a few of the tuberous roots from your last crop, or buy untreated sweet potatoes from your local farmer's market. Six weeks or longer before planting outdoors, place them into a box of moist sand, chopped leaves, or sawdust and keep at 75-80 degrees F. When shots are 6 to 9 inches long, cut them off the root. Put root end into rooting compound and plant root end into soil. Continue to root slips until planting time.
Planting Sweet Potatoes in Tires
Sweet potatoes will grow in poor soil, but they will become deformed if planted in heavy clay or long and stringy if planted in sandy soil. I plant my sweet potatoes in aged sawdust mixed with small amounts of clay soil. I place tires two high in a sunny location around the garden's edge.To create the perfect environment, I fill tires with sawdust and clay mixl in the tires and mix in plenty of compost. I do not add any extra fertilizers. I plant 2-3 slips up to the top leaves into each tire and press gently but firmly into soil. I then generously water the contents of the tires.
Care For Sweet Potatoes During The Growing Season
Allow your sweet potatoes to grow in the sunny location from the time you plant until the day frost kills the leaves. Water generously throughout the season. Be sure that plants get at least one inch of water each week throughout the season.
In the south, sweet potato weevils are a problem and can puncture stems and tubers to lay their eggs. They attack the leaves and stems and can also spread foot rot which creates enlarged brown or black areas on the stems.
Fungal diseases include "black rot". Black rot produces circular, dark depressions on the tuber. Throw away infected potatoes. Small round dark spots on the tubers, however are not black rot, but are scurf. Scurf does not affect eating quality.
Another enemy "stem rot" can be controlled by using certified disease free slips and by rotating the crop. White hellebore planted nearby controls a number of leaf eating insects. If rabbits are eating the plant leaves, spray with either fish emulsion or a liquid kelp solution.
Harvest and Storage
Harvesting Sweet potatoes grown in tires is so easy. Simply kick over the top tire and simply pick up the sweet potatoes. Dry sweet potatoes for several hours in the sun, then move them to a well ventilated area and keep at 85-90 degrees F for ten to fifteen days. After cured, store at about 55 degrees at 75-80 percent humidity. They will store for several months.
© 2013 Donna Brown