Here are some general hints that will help your plants get off to a good growing start and increase your chances of a bountiful harvest.
Receiving Your Potato Plants
Heavy plant foliage is sometimes trimmed to prevent over-heating during shipment. Many large Sweet Potato Farmers cut off all the leaves and a part of the plant's roots. Expect your plants to appear wilted or possibly bleached to a higher color due to their enclosure during shipment, but do not be alarmed if either condition exists. Sweet Potato plants are very tough, and if planted properly and favorable weather exists, your plants will grow well and yield an abundant harvest.
If there is to be a delay in planting, remove the plants from the carton and take the rubber band, waxed paper and moss away from the roots. Then place the roots in a position where they can receive moisture, being careful to keep the plants away from the sun and wind. Do not wet the stems or leaves. Roots placed on wet sawdust or moss or on a wet burlap bag will keep the plants strong and healthy for several days.
Planting Sweet Potatoes
"Set" plants as soon as possible after you receive them. The ideal time is late in the afternoon after the hot sun has gone to bed. Try to avoid setting plants on a windy day. Hold your plants until the following day and the results will be much better.
Sweet Potatoes prefer a sandy loam soil that drains well, but they grow in all types of soil in all 50 states. Loose, freely worked soil will give the potatoes a chance to become large and smooth. The use of fertilizer is the gardener's choice. Some say the taste is better without fertilizer, others say the yield is better when you use fertilizer.
Sweet Potatoes should be planted in elevated rows 8 to 12 inches tall and Garden rows should be about 3 feet apart. The higher the row the more space the potato has to develop. Plants should be set 10 to 18 inches apart within the rows. Evenly spaced rows and plants will produce a more uniform-sized potato. A "peg", shovel or stick or can be used to set your plants. Place the roots well in the ground but do not cover the bud. Pour a little water in the plant hole around the roots and then firm up the soil. In case frost or unexpected cool moves in, protect your plants with a light cover.
Cultivation and Maturity
Keep the soil around the plants weeded and worked to a fairly loose condition. Once the plants get started, the plant growth will smother out most grass and weeds. Maximum maturity is hard to determine as some people like a small Potato, which they call a "baby baker." Others desire the Potato to grow to its largest or "jumbo" size. Simply examine an average hill and dig the potatoes when they approach the size that you desire.
Optional Black Plastic Method
Many folks in northern states have been growing Sweet Potatoes for years. Now, new Quick-maturing varieties along with new gardening techniques that have been tested for several years in the New England states have helped harvests almost double. These yields nearly match those from Louisiana, Georgia and North Carolina, which are traditional Sweet Potato states.
Prepare a large row about 12 inches tall and make a furrow about 2 inches deep in the middle of the ridge. Cover the row with black plastic. This can be done 2 weeks before planting time and the soil will be warmed and your plants will begin to grow immediately after they are put in the soil. The large row of loosely worked dirt helps the potatoes grow large and smooth.
When you are ready to plant your potatoes (late afternoon if possible), use a knife to make small planting slits in the plastic. Slits every 12 inches will be about the right distance for average sized Potatoes. If larger potatoes are desired, the slits should be 15 to 18 inches apart. Put the roots of each plant in a hole made under each slit and pour about a cup of water around the roots. Then use your hands to firm up the dirt around the roots. Protection is needed when unseasonable cool is expected. Gardeners in the south to mid-section of the country may want to remove the black plastic about a month after planting.
Use care in digging your potatoes, being careful not to cut or bruise them. A shovel or large pronged fork is ideal to use. With a loose row just pull the dirt away with your hands and gently place your beautiful potatoes in a ventilated storage basket or crate and start selecting your favorite recipes.
Place your ventilated crates or baskets of freshly dug potatoes inside a building. Let the potatoes dry out or air for 8 to 10 days. This helps to heal cuts and the bruises that may have occurred and toughens the skin for winter storage. The rich, black soil of some gardens may cause discoloration on the outside skin of some potatoes. Do not be alarmed, storage life and taste have not been affected. After the potatoes are dried out, place them in a permanent storage area where the temperature ranges from 50 to 60 degrees F. While your potatoes are in storage, avoid unnecessary handling. Just cook the potatoes as you come to them from the top of the storage container to the bottom.
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