Michigan State University Extension has these tips for winter storage of homegrown potatoes: Toughen up potatoes for storage before harvest by not watering them much after they flower.
Let the potato plants and the weather tell you when to harvest them. Wait until the tops of the vines have completely died before you begin harvesting. When the vines are dead, it is a sure sign the potatoes have finished growing and are ready to be harvested. Dig up a test hill to see how mature the potatoes are. The skins of mature potatoes are thick and firmly attached to the flesh. If the skins are thin and rub off easily, your potatoes are still too new and should be left in the ground for a few more days.
Green potatoes have a bitter taste and if enough is eaten can cause vomiting and diarrhea. Small spots can be trimmed off, but if there is significant greening, throw the potato out. An interesting place you might not be aware of is the potato museum in Washington, D.
As you dig, be careful not to scrape, bruise or cut the potatoes. Damaged potatoes will rot during storage and should be used as soon as possible. After harvesting, potatoes must be cured. Let them sit in temperatures of 45 to 60 degrees Fahrenheit for about two weeks. Then, a crew picks and grades the storage roots by hand and put them in boxes accordingly. The crew uses gloves to minimize skinning. Large growers use more mechanized harvesters, in which the chain digger takes the storage roots up to a platform where the crew select the roots by size and put them in boxes.
Another type of harvester includes rollers spaced according to the standard sizes to separate the storage roots and drop them into large boxes or bins. Figure 2 Chain digger dropping sweetpotato storage roots after sieving the soil through the chain. Postharvest conditioning is necessary to enhance fast healing and reduce losses to decay and moisture loss because of injuries as well as to improve culinary attributes sweetness, flavors, etc.
Curing helps to speed up the healing of wounds that occur during harvest, preventing shriveling and reducing the risk of rot during storage. Curing also makes the sweet potato more palatable by converting starches to sugars and improving aroma and texture.
The aesthetic appearance of storage roots depends on how fast the roots are put in curing conditions to generate a new skin similar to the original figure 3. A delay in curing may cause the wound to dry out leaving unappealing scars. Figure 3 Wound healing and generation of new skin: sunken dry wound scars left and new skin generated when curing immediately after harvest right.
The size depend on the volume and length of the harvest period. The rooms should be large enough to hold the volume of days of harvest and then close it to complete the curing period. Roots should be kept in a dark, cool place after curing. Some growers reduce the relative humidity to promote skin set and toughness before washing and packing for delivery to markets.
Reducing the humidity too early promotes moisture weight loss. Variety, location and management influence sweet potato yield and proportion of root sizes. With acceptable management practices, yield may range from to bushels 50lb per acre of U. Columbus likely encountered sweet potato in his early voyages to the West Indies but it was not until his fourth voyage to Yucatan and Honduras that he recorded its discovery in his journals.
He is credited with its introduction to the New World Spain in about and a number of different types were cultivated there by the mids. Sweet potato was grown in what is now Virginia as early as From there it was taken both north and south. Native Americans were known to have grown sweet potato extensively by the s and soon thereafter it became a popular staple of the South.
Even today, sweet potato is much more popular in the south than the north as a food. Although sweet potato skin color varies fairly extensively among cultivars, flesh color is either white or dark orange.
The white-fleshed types usually are drier in consistency and originally were favored in northern areas of our country. Yams Dioscorea species are perennial herbaceous vines cultivated in tropical regions of the world for their starchy tubers. Yams are still mainly a curiosity in the United States. As mentioned previously, sweet potatoes usually are harvested after the first frost of the fall season.
The latter is likely to do considerable damage the leaves. However, the roots remain unharmed, but should be dug as soon as possible following the frost.
Sweet potato roots have thin skins and bruise easily. Therefore, care should be taken when harvesting them. Using a potato fork, gently lift the roots from the soil. Any soil that remains on the roots after they have been dug should be removed.
Also, it is a good idea to let the freshly-dug roots dry atop the soil in the sun for several hours before proceeding further.
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