Planting: Moist well drained soil in sun, fully hardy perennial, 18". Plant in early spring. Dig a trench 3-4" mounding the earth on the sides. Cut tubers so that there is 2-3 eyes in each piece, and place them in the trench about 6" apart. Cover with about 1" of soil. As the greens emerge, continue to cover with soil.
Harvest: Potatoes are ready for harvesting when the green tops die back. They can be left in the ground and dug as needed until before the ground freezes. Store in paper bags in the cellar.
Culinary: Any which way.
Medicinal: See below.
Nutrition: Nutritionally, potatoes are best known for their carbohydrate content (approximately 26 grams in a medium potato). The predominant form of this carbohydrate is starch. A small but significant portion of this starch is resistant to digestion by enzymes in the stomach and small intestine, and so reaches the large intestine essentially intact. This resistant starch is considered to have similar physiological effects and health benefits as fiber: it provides bulk, offers protection against colon cancer, improves glucose tolerance and insulin sensitivity, lowers plasma cholesterol and triglyceride concentrations, increases satiety, and possibly even reduces fat storage (Cummings et al. 1996; Hylla et al. 1998; Raban et al. 1994). The amount of resistant starch in potatoes depends much on preparation methods. Cooking and then cooling potatoes significantly increases resistant starch. For example, cooked potato starch contains about 7% resistant starch, which increases to about 13% upon cooling (Englyst et al. 1992).
Potatoes contain vitamins and minerals that have been identified as vital to human nutrition. Humans can subsist healthily on a diet of potatoes and milk; the latter supplies Vitamin A and Vitamin D.[22]A medium potato (150g/5.3 oz) with the skin provides 27 mg of vitamin C (45% of the Daily Value (DV)), 620 mg of potassium (18% of DV), 0.2 mg vitamin B6 (10% of DV) and trace amounts of thiamin, riboflavin, folate, niacin, magnesium, phosphorus, iron, and zinc. Moreover, the fiber content of a potato with skin (2 grams) equals that of many whole grain breads, pastas, and cereals. Potatoes also contain an assortment of phytochemicals, such as carotenoids and polyphenols. The notion that "all of the potato's nutrients" are found in the skin is an urban legend. While the skin does contain approximately half of the total dietary fiber, more than 50% of the nutrients are found within the potato itself. The cooking method used can significantly impact the nutrient availability of the potato.
Almost all the protein content of a potato is contained in a thin layer just under its skin.[citation needed] This is evident when the skin of a boiled potato is carefully peeled; it appears as a yellowish film. For maximum utilisation of this small, but valuable dietary source of protein, potatoes should be consumed whole, or peeled after cooking.
Potatoes are often broadly classified as high on the glycemic index (GI) and so are often excluded from the diets of individuals trying to follow a "low GI" eating regimen. In fact, the GI of potatoes can vary considerably depending on type (such as red, russet, white, or Prince Edward), origin (where it was grown), preparation methods (i.e., cooking method, whether it is eaten hot or cold, whether it is mashed or cubed or consumed whole, etc), and with what it is consumed (i.e., the addition of various high fat or high protein toppings) (Fernandes et al. 2006). (Source: Wiki)
Toxicity: Potatoes contain glycoalkaloids, toxic compounds, of which the most prevalent are solanine and chaconine. Solanine is also found in other plants, mainly in the mostly deadly nightshade family, which includes a minority of edible plants including the potato and the tomato, and other typically more dangerous plants like tobacco. This poison affects the nervous system causing weakness and confusion.
These compounds, which protect the plant from its predators, are generally concentrated in its leaves, stems, sprouts, and fruits.[31] Exposure to light, physical damage, and age increase glycoalkaloid content within the tuber;[32] the highest concentrations occur just underneath the skin. Cooking at high temperatures (over 170 °C or 340 °F) partly destroys these. The concentration of glycoalkaloid in wild potatoes suffices to produce toxic effects in humans. Glycoalkaloids may cause headaches, diarrhea, cramps and in severe cases coma and death; however, poisoning from potatoes occurs very rarely. Light exposure causes greening(chlorophyll synthesis), thus giving a visual clue as to areas of the tuber that may have become more toxic; however, this does not provide a definitive guide, as greening and glycoalkaloid accumulation can occur independently of each other. Some varieties of potato contain greater glycoalkaloid concentrations than others; breeders developing new varieties test for this, and sometimes have to discard an otherwise promising cultivar.
The toxic fruits produced by mature potato plants
Breeders try to keep solanine levels below 200 mg/kg (200 ppmw). However, when these commercial varieties turn green, even they can approach concentrations of solanine of 1000 mg/kg (1000 ppmw). In normal potatoes, analysis has shown solanine levels may be as little as 3.5% of the breeders' maximum, with 7–187 mg/kg being found.[33]
The US National Toxicology Program suggests that the average American consumes at most 12.5 mg/day of solanine from potatoes (the toxic dose is actually several times this, depending on body weight). Dr. Douglas L. Holt, the State Extension Specialist for Food Safety at the University of Missouri, notes that no reported cases of potato-source solanine poisoning have occurred in the U.S. in the last 50 years and most cases involved eating green potatoes or drinking potato-leaf tea. (Source:Wiki)
Third Eye Vision:
Seeded: Tubers planted Spring 2009, 3 patches in garden
Links: Wiki
Sources:
The Royal Horticultural Society New Encyclopedia of Herbs and Their Uses (RHS)
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