Gardening Articles: Edibles :: Vegetables
by Deborah Wechsler
To all the reasons you might choose one vegetable variety over another--appearance, flavor, yield, pest resistance, or regional adaptation--now you can add enhanced nutrition. The vegetables you'll read about here aren't just good for you. They've been bred to be better for you.
As nutrition research makes clearer each year, good foods are the best way to supply nutrients to our bodies. So naturally, a vegetable's nutrient content is becoming an important measure of its value. Research is also showing that fruits and vegetables provide us with important disease-fighting chemicals. So it makes sense that plant breeders would focus on making vegetables even more healthful.
Needless to say, home gardeners are best positioned to take advantage of these breeding advances. None of these varieties are any more difficult to grow than older ones, and most are readily available.
Carrots and Carotenes
Researchers have gradually increased carotene levels over the years, says Phil Simon, a USDA plant geneticist at the University of Wisconsin, Madison. As recently as 1980, a typical hybrid carrot had 80 to 100 parts per million (ppm) of carotene. New high-carotene varieties have twice as much, and breeders are testing varieties that have up to 500 ppm.
Although dark, leafy greens, sweet potatoes, and winter squash are all good sources of carotene, carrots are the champs. If these carotene-rich carrots were widely available, the positive impact would be immense, because Americans rely upon carrots for most of their dietary vitamin A. "With some standard varieties, you'd have to eat 1 to 2 pounds of carrots a day to meet your dietary needs," Simon points out. "By comparison, you only need to consume as little as half a carrot of a high-carotene variety to meet your dietary need."
By the way, don't worry about eating too many carrots. While too much vitamin A in pill form can be harmful, you can't consume too much carotene. Your body just takes as much as it needs to make vitamin Aand discards the rest. (Notable exceptions are babies and those individuals with an extra sensitivity to carotenoids: Too many carrots can make their skin turn orange.)
An unusually colored, nutrient-enhanced carrot will reach supermarkets in 1997. At Texas A&M University, researchers have developed a purple-skinned, orange-cored carrot named 'BetaSweet', with carotene levels of 180 to 220 ppm. It will be test-marketed as precut slices or "BetaBites". If you see them in the stores, give them a try and decide if you want to grow them; seeds will become available to home gardeners in 1998 or 1999.
In the meantime, here are three high-carotene carrots you can grow now. The number of days until harvest after sowing seed is listed in parentheses.
'Ingot' (63 days). This 6- to 8-inch-long, blunt-ended, Nantes-type hybrid carrot has a sweet flavor. Its carotene levels are between 120 and 170 ppm.
'Beta Champ' (74 days). This Imperator-type hybrid has 10-inch-long tapered roots. It is great for juicing. Testing shows it consistently contains 150 to 270 ppm carotene.
'Healthmaster' (110 days). These large, 3-inch-diameter, 10-inch-long, hybrid Danvers-type carrots take a long season to mature but are sweet-tasting. Carotene levels are between 60 and 95 ppm, about 35 percent higher than levels in older, open-pollinated Danvers varieties.
What about carrot flavor? Unfortunately, says Simon, when his team started selecting for high carotene levels, it didn't simultaneously select for flavor. High-carotene carrots tend to also be high in turpenoids, which can make some carrots strong-tasting and bitter. "I'd have to say that the flavor of most of these high-carotene carrots is just average. But the genetics of the two characteristics are independent, and there's no reason superior flavor can't be bred in." John Navazio, vegetable breeder at Chriseeds in Mount Vernon, Washington, agrees. "I'm working on some material with over 250 ppm that will have great flavor and great eating quality."