Garden Crops to Dig
Harvesting root crops is like digging for buried treasure, and banking them in the root cellar is akin to saving money for a rainy day. Maybe they aren’t as glamorous as artichokes and radicchio, but carrots, beets, parsnips, radishes, rutabagas and turnips are staples people have depended on for thousands of years. Often referred to as lowly vegetables, root crops have recently enjoyed a renaissance.
They are among the first and last vegetables to mature – think radishes to rutabagas. They’re ideal for gardens in cool short season regions because they have no definite stage of maturity, and they’re perfect for small gardens – or even containers – because they take up little space. All root vegetables prefer a deep, loose soil that retains moisture yet is well-drained. Root crops do not grow well in very acid soils (pH 6 to 6.5 is ideal), and all are best seeded directly into the garden.
Native to Afghanistan, cultivated carrots belong to the Umbelliferae family that includes parsley, fennel and anise. They made their way to China in the 15th century. Like most root crops, carrots are biennials that normally require two growing seasons to produce flowers and seeds. Since we eat the roots before the plant matures, we never see that final growth stage. The orange varieties Americans favor came from a yellow mutation in the Netherlands in the 16th century. Today, new carrot varieties are bred to be high in beta-carotene – a powerful antioxidant that is converted into vitamin A after eating. The darker the orange color, the more beta-carotene the carrot in question contains. The saying that carrots are good for your eyes isn’t just an old wives’ tale. Vitamin A helps us see in dim light and can help prevent night blindness.
Carrots are among the easiest vegetables to grow, harvest and store. Vermont gardener Edward C. Smith, author of The Vegetable Gardener’s Bible, says soil preparation and moisture are key. He grows carrots in raised beds that he has dug deeply. “The thing you’ve got to watch out for with carrots is rocky soil,” says Smith. “Any time a carrot runs into an obstruction, it will split in two and start growing two shoots. And the soil needs to be very fine because those tiny seeds have to be in contact with moisture to germinate.” Smith waters his seed bed with a gentle spray at least once a day. I’ve sprinkled Jiffy Mix (a commercial seed starting soil composed of sphagnum and perlite) on top of my carrot seeds and covered them with a strip of floating row cover to keep them from getting washed away by heavy rain.
Carrots are by far his customers’ favorite vegetable, says Rob Johnston, owner of Johnny’s Select Seeds in Albion, Maine. “I love good storage carrots,” he says, “and the best one for storage is ‘Bolero,’ a variety that is resistant to blight.” Territorial Seeds’ horticulturist Josh Kirschenbaum’s favorite carrot is ‘Mokum,’ a combination of ‘Nantes’ and ‘Emperator’ types that performs well in the company’s Oregon trial gardens. Renee Shepherd of Renee’s Garden Seeds really likes the new varieties of colored carrots, and she stores them in the ground all year in her Zone 7-8 gardens in Felton, California.
Here in northern Minnesota, we store our carrots in damp sand in a cool room where temperatures hover near 40ºF. When he can count on snow, Smith just mulches his carrot bed heavily with straw and covers it with fencing to keep deer out. “We can go out in January, pull back the mulch and those carrots are the tastiest ones you’ll ever eat,” he says.
Ancient Romans once considered beets a remedy for snakebite, and the inedible white beet still grows wild along the Mediterranean coast. By 1821, beets were common in America, and women often used the juice from a cut red beet as rouge for their cheeks. Members of the goosefoot family that includes spinach and Swiss chard, most beets are globular or cylindrical. “Red as a beet” is not always true any more. Kirschenbaum’s favorite is ‘Touchstone Gold,’ a golden beet with outstanding flavor, but he also admires the dark maroon foliage of ‘Bull’s Blood’ beets. ‘Chioggia’ is an Italian beet with red skin and interior of alternating white and pink stripes.
Beet seeds are not seeds at all but rather a dried fruit that may contain one to six seeds; consequently they always need thinning. Instead of pulling the extra seedlings, Smith cuts them off with scissors. “What’s left behind is food for soil microbes, organic matter that they can immediately add to their diet,” he says. Since beet roots can grow as much as three feet into the soil, it is important to dig the bed deeply. Although beets will tolerate some shade, they grow best in full sun. Plant them as soon as soil can be worked in the spring.
Beets have the highest sugar content of any vegetable, but they are very low in calories. Equal amounts of beets have as much potassium as potatoes, and cooked beet greens have more iron than a hamburger patty. Be sure to leave the skin on and an inch of leaf stem when cooking beets to prevent bleeding of the red pigment. While Shepherd admits beets are not the vegetable she would choose if she were marooned on a desert island, she loves to roast beets. Her favorite beet recipe from her Recipes from a Kitchen Garden cookbook is a beet and green apple salad. Mine is for my mother’s pickled beets.
Some say parsnips resemble an anemic wild carrot, rough and dirty-white. Those who enjoy them say their sweet, nutty flavor and mild celery-like fragrance make up for their unimpressive appearance. Native to Eurasia, this homely vegetable has been grown since Roman times when it was considered an aphrodisiac. Parsnips were used as a sweetener before the development of the sugar beet, and pigs bred for the best-quality Parma ham in Italy are still fed parsnips.
Closely related to carrots, parsnips are richer in vitamins and minerals, potassium and fiber. Their color indicates they are low in beta-carotene, and they are also low in calories depending on how they are cooked. My favorite method is to boil them until they are tender and then sauté thin slices in butter.
Like carrots, parsnip seeds are slow to germinate, taking as long as three weeks. To speed germination, some gardeners soak the seeds overnight or pre-sprout them indoors. And the seed seldom remains viable longer than a year, so it’s best to purchase fresh seed each season. Sow the seeds in early spring as soon as the ground can be worked or when daffodils bloom. Smith’s favorite variety is ‘Harris Model’ for the smooth texture and exquisite flavor.
Don’t harvest parsnips until after the first frost, which is when they develop their characteristic sweet flavor. Even in our Zone 3 climate, we’ve left parsnips in the ground through the winter and harvested them in the spring. Parsnips will keep for weeks stored in a very cool place. Rob Johnston has a root cellar in his basement with a cement floor, cinder block walls and a small window. To keep the humidity up, he tosses cupfuls of water on the walls and adjusts the window to maintain ideal temperatures of “freezing-but-not-below.”
The radish is the most popular and the best selling vegetable in Japan, but the variety is called ‘Daikon’ that can weigh as much as 70 pounds. Radishes are one of the most ancient of cultivated vegetables, dating back to the 7th century B.C. in China. Egyptian pharaohs held the radish in such high regard that they fed them to slaves building the pyramids. The Romans called this vegetable radix, one of the words for “root” and “radical.” All radish species belong to the mustard family, which also includes broccoli and watercress.
Two hundred varieties of radishes are available in colors ranging from lavender to green to black, but most familiar are small red radishes with white flesh. Round radishes can be as small as marbles or as large as baseballs. Johnston likes ‘Cherriette,’ and Kirschenbaum’s favorite is a variety called ‘Red Meat.’ “It’s also known as a watermelon radish,” Kirschenbaum says, “because it has a white outer skin and a pink blush in the interior. When I tasted this radish, I swear it had a hint of ranch dressing on it.” The ultimate guilt-free snack, a 3-ounce radish contains only 20 calories because it is 94 percent water. Radishes have nearly as much potassium as bananas and half the vitamin C of oranges.
Radishes like a sunny location and loose, even sandy, well-drained soil. “To grow radishes well,” Smith says, “you have to grow them fast and harvest them fast. Sometimes it can only be a day or two between a really good radish and a worthless radish. If you leave them in the ground too long, they develop a sharp taste and pithy texture followed by split roots.” Many radishes are ready to harvest in 21-30 days. When his radishes reach the right size, Smith harvests all of them and stores them in the refrigerator. To enjoy radishes all season, plant some seeds every week to 10 days.
Root maggots are the bane of the radish crop. Avoid planting this vegetable where members of the cabbage family were grown in the past three years. Cover newly seeded rows with a fabric row cover like Agribon or Reemay to prevent flies from laying the eggs that become root maggots.
Turnips and Rutabagas
In her book, The Garden Primer, Barbara Damrosch says, “There is nothing in the garden as unromantic as a turnip, unless perhaps it’s a rutabaga. Strong-flavored, good-storing root vegetables, they are rarely invited to sit at formal tables. But they are good, earthy peasant food.” Considered twins by some for their similar appearance, culture requirements and taste, they are actually two completely different species. Recent botanical detective work discovered a hybridization occurred long ago between some forms of cabbage and turnip resulting in the new species, the rutabaga.
Turnips are ancient, having been cultivated by the Romans at the beginning of the Christian era and growing wild in Siberia today. They are one of the most common garden vegetables in America since colonial times. The rutabaga was first found in Europe some time in the late Middle Ages. Some claim they are native to Sweden, and they are sometimes called ‘Swedes’ since they get their name from the Swedish rotabagge. Others think rutabagas originated in Finland or Siberia in the early 17th century. They are a staple crop in Europe.
Rutabaga leaves are smooth while those of turnips are rough and hairy. Rutabaga flesh is most often yellow whereas turnip flesh is white. Turnips are rich in vitamins and fiber; rutabagas are high in beta-carotene. Harvest turnips when the roots are 2-3 inches in diameter and rutabagas when their roots are 4-5 inches. Both store well in the refrigerator.
Turnips are a short-season crop maturing in two months, so plant them in the spring, late summer or fall for roots or greens. Rutabagas require four weeks longer to mature, so plant them as early in the season as possible for fall harvest. Because both are in the same family as radishes, protect them against root maggots with row covers when you plant the seeds.
Consider root crops when you plan your next garden. These under-appreciated, subterranean beauties make nutritious additions to soups and stews. They are loaded with carbohydrates and dietary fiber, rich in flavor and easy on the pocketbook.
Margaret Haapoja grows root crops and more at her home in Bovey, Minnesota.
Recommended Root Crop Varieties
Carrots: ‘Mokum,’ ‘Bolero,’ ‘Purple Haze’
Beets: ‘Touchstone Gold,’ ‘Chioggia,’ ‘Bull’s Blood’
Parsnips: ‘Gladiator,’ ‘Javelin,’ ‘Harris Model’
Radishes: ‘Cabernet,’ ‘Red Meat’
Rutabagas: ‘Marian,’ ‘Laurentian’
Turnips: ‘Purple Top White Globe,’ ‘Hakurei’
Root Crop Seed Sources
Johnny’s Selected Seeds
955 Benton Ave.
Renee’s Garden Seeds
6116 Highway 9
Felton, CA 95018
Territorial Seed Company
P.O. Box 158
Cottage Grove, OR 97424
Phone Orders: 800-626-0866
Fax Orders: 888-657-3131
Good Root Crop Reads
The Garden Primer, Barbara Damrosch, Workman Publishing, New York, 1988.
The Vegetable Gardener’s Bible, Edward C. Smith, Storey Publishing, North Adams, Massachusetts, 2000.
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