Pick Pa.’s best root crops
Root crops have long been popular with gardeners. While our ancestors dug wild roots to supplement their diets, modern humans have spent decades breeding and selecting root crops to develop the delicious and nutritious root crops we grow today.
Many root crops contain a broad diversity of vitamins and minerals, in addition to fiber and essential amino acids, making them high in nutritional value, too.
Root crops are also among the easiest vegetables for gardeners to grow. They’re fairly straight forward to cultivate and are susceptible to a limited number of pests.
As long as you properly prepare the planting site and pay attention to the varieties you’re growing, successful root crop cultivation is close at hand
Soil prep: Since the edible portion of root crops extends well beneath the soil surface, it’s imperative to break up heavy soils and add plenty of quality organic matter (such as compost or well-rotted manure) to the planting site. This creates the well-drained, loosely structured soils they covet. Cultivating the soil to a depth of 18 or more inches allows the roots to penetrate deeply.
Root crops thrive in a pH range between 6 and 7, and they use high amounts of phosphorus, with only moderate nitrogen use (over application of nitrogen fertilizers encourages lots of top growth at the sacrifice of large, well-formed roots). Since phosphorus doesn’t readily travel in the soil, the zone from which your plants can absorb it is relatively small and quite close to the root itself. To a gardener, this means that, should a soil test indicate the need for phosphorus, it should be applied as a side-dressing to each row of root crops. My favorite sources of organic phosphorus are rock phosphate and bone meal.
Pick the right varieties: It’s important to choose the best varieties for your climate when growing root crops. Look for cultivars with noted resistance to pests and disease, and for varieties that are known to thrive in your growing conditions. Many modern hybrids can be good choices. They’ve been bred for uniform shape, size and disease resistance. If those are the qualities you value, choose hybrids. But, don’t forget that heirloom varieties are a great choice for true, down-home vegetable taste. Plus, heirloom root crops offer wonderful colors and textures that may be missing in modern hybrids.
Fun choices: While most gardeners are familiar with orange carrots and red beets, here are some other wonderful root crop choices that are both delicious and easy to grow. Most are quite simple to grow from seed planted directly into the vegetable garden or containers. There’s no need to start the seeds of root crops indoors, under grow lights, because the required growing season for most of these vegetables is relatively short, allowing us to plant the seeds in spring and make a harvest just a few weeks later.
Current favorites include “Detroit Dark Red,” an all-purpose winner from 1892, “Chioggia,” an Italian heirloom with pink and white concentric rings (often called a “bullseye beet”) and “Golden,” a variety from the 1820s with rich, orange flesh and a mild, sweet taste.
Since what appears to be a single beet seed is actually a cluster of many seeds, it’s important to space beets properly. Even so, be prepared to thin the seedlings. New strains have recently arrived on the market that produce only one plant per seed (monoseeded), including a variety called “Moneta,” reducing the need for the time-consuming task of thinning.
The precursors to modern carrots were white, purple, red, yellow or green and had relatively tough, small roots. Today’s orange carrot was bred in Holland around the 16th century when breeders focused on promoting the orange, beta-carotene rich color.
There are literally hundreds of carrot varieties available to growers, and though many of them are orange, you’ll also find yellow, red, white and purple rooted varieties, including “Yellowstone,” “Cosmic Red,” “Snow White” and “Purple Dragon,” to name just a few.
Note that carrots take quite some time to germinate, so be patient. It can take up to three weeks for carrot seedlings to break through the soil. Thinning young carrots provides ample space as they mature and is essential for producing long, straight roots.
Today’s most common turnips, like “Purple Top White Globe” and “White Egg,” have crisp, white flesh with a smooth, mild taste. Golden varieties, including “Golden Globe” and “Golden Ball,” have a very delicate flavor and are beautiful roasted or served in soups.
In my garden, turnips do best planted as a late-season crop. I sow the seeds in mid-August and harvest the roots in the autumn, after they’ve been exposed to a few hard frosts. Cold temperatures convert the starches found in the root into sugars, making them sweet and extra tasty.
The thick, fleshy, bulbous rutabaga root thrives in colder climes and is rich in beta carotene. Rutabagas are very delicate and fresh tasting, often a surprise to first-timers who see them only as a lowly, boring vegetable. They are delicious grated raw in salads, roasted, mashed or stewed.
“American Purple Top” is an early 1900s heirloom and “Laurentian” is an improved version of the variety. It’s best to let all rutabagas mature to 4-5 inches in diameter. Like turnips, a few light frosts will sweeten the flesh of rutabagas. Their relatively long maturation time is something to take into account when planting.
Though they aren’t highly popular here in the US, parsnips are a sweet and starchy root vegetable. Long tapered roots, similar in appearance to carrots, are creamy white and the plant tops are ferny and light. Cooks across Europe have long appreciated their frost-enhanced sweetness through the winter months.
Parsnips are seeded in the spring and take 4 or 5 months to mature. Exposing full-grown parsnips to cold temperatures, either in the ground or in the fridge, turns their starch to sugar and sweetens them perfectly. In many parts of the country, including here in Pittsburgh, parsnips can be left to over winter in the soil and pulled as needed throughout the colder months.
“French Breakfast” has long been my favorite radish variety, but “Chinese Red Meat” watermelon radish has recently displaced it. This old variety has beautiful pink flesh with a pale green skin. It’s great for fall sowings and measures 4 inches across. If you’d like a more traditional radish, try “Easter Egg” blend, which is a mixture of pink, fuchsia, red, white and purple skinned radishes.
Since radishes prefer cooler soil and air temperatures, sow them as soon as the spring soil can be worked and harvest about 30 days later. Fall sowings also do well in Pennsylvania; sow the seeds in early to mid-August and harvest well into autumn.
Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio with Doug Oster. She is the author of several gardening books, including “Attracting Beneficial Bugs to Your Garden,” “Good Bug, Bad Bug,” and her newest title, “Container Gardening Complete.” Her website is jessicawalliser.com. Send your gardening or landscaping questions to firstname.lastname@example.org or The Good Earth, 622 Cabin Hill Drive, Greensburg, PA 15601.