Cultivating something old, but new to our gardens, is a wonderful way to connect with our ancestors—or in this case, with our “roots.” And daikon, celeriac, salsify, and scorzonera are root vegetables with old-world associations. Although common in European or Asian cooking, these crops barely register with American gardeners today. What a shame: All four offer nutritious top greens as well as flavorful roots that extend the harvest season well into winter. It’s time more gardeners tried these honorable heirlooms.
Salsify and Scorzonera
The young leaves of salsify and scorzonera are edible, and their flower stalks can be blanched and served as you would asparagus. Yet it is the roots that are most prized by gourmets. Salsify produces pale-skinned, often forked roots with tiny rootlets, while scorzonera resembles a petrified brown carrot without the taper; preparing the long, slender roots requires some effort. Both vegetables are southern European natives, widely cultivated in the United States during the 18th century but largely absent from seed catalogs today. They are readily available in European produce markets during the late fall and winter months, a tribute to old-world traditions.
“We grow salsify and scorzonera as an ornamental crop,” says Doug Croft, horticulturist at Chanticleer, a public garden near Philadelphia where the vegetable garden is more about design than harvest. Transitioning from a summer garden to fall often leaves gaps in the rows, but Croft discovered that salsify produces a brilliant green rosette during the fall months when many other vegetables are past their prime. “As a bonus, the plants send up flower stalks with gorgeous composite flowers,” Croft says. As biennials, the plants bloom in their second year: purple flowers for salsify and yellow for scorzonera.
Salsify (Tragopogon porrifolius) and scorzonera (Scorzonera hispanica) are members of the aster family, Asteraceae, and share similar flat leaves. Scorzonera has a flavor reminiscent of artichoke heart. It is a common vegetable in early cookbooks, served grated, buttered, scalloped, or stewed. Thomas Jefferson grew salsify at Monticello, planting it in the same quantities as carrots and asparagus. Its flavor has been compared to that of oysters; in fact, salsify is sometimes called oyster plant.
Both vegetables are easy to grow from seed. A few varieties exist for each type, yet the differences are minimal.
How to grow:
Soil that is moderately rich and on the sandy side is ideal for these and other root crops. Amend poor soil with well-composted manure or leaf mold, worked into the top 9 inches. Sow seeds directly in the garden in early spring. Thin the seedlings to stand 4 inches apart. Apply mulch between rows to keep the soil moist and to eliminate weed competition.
Use a garden fork to lift the roots when the plants have completed their growth in October. Dig carefully, because the roots are brittle. To store in a root cellar at about 32°F, first brush off loose soil and twist off the tops. Pack in damp sand to keep the roots from shriveling. An easier storage technique, if the soil is light and dry, is to leave the roots in place through winter beneath an insulating layer of loose straw, and dig up only as needed.
Photos: Thomas MacDonald, top salsify, bottom scornonera
Celeriac develops a pitted and whorled exterior that, when peeled away, reveals a soft, creamy white interior with a mild, herbaceous flavor. This Mediterranean native is popular in Europe. Gardeners and cooks in the United States largely ignored it until recently, when it began appearing on menus as a classic French salad, coarsely grated and dressed with rémoulade, or in potato leek soup.
Celeriac, also called celery root or knob celery, belongs to the same species as the common celery grown for its stalks—but is easier to grow. A cousin of carrots, parsley, and parsnips, celeriac (Apium graveolens) is a long-season crop, taking a minimum of 115 days from seed to a harvestable knob up to 4 inches in diameter. It needs well-fertilized soil and consistent moisture throughout the growing season to prevent bolting, misshapen roots, or black heart, a calcium deficiency that riddles the interior with dark mottled lines. The attractive leafy tops form a low mound, remain green from spring until fall, and can be harvested sparingly to season soups and stews.
Celeriac’s mild flavor easily blends with and enhances other vegetables. It is a boon to those on a diet: Boil and mash the low-starch knobs with an equal measure of potatoes for a dish with fewer calories than mashed potatoes. For a refreshing salad to serve alongside a hearty entrée, grate or thinly slice celeriac, then toss with rémoulade, a mustardy mayonnaise seasoned with fresh chopped tarragon.
Cultivars vary slightly in size, days to maturity, and reliability. ‘Brilliant’ and the European cultivar ‘Diamant’ are commonly available.
How to grow:
Sow seeds indoors 8 to 10 weeks before transplanting outdoors in late spring. Keep soil moist and temperatures at 65°F to 70°F while seeds are germinating; they can take 2 to 3 weeks to emerge. Move seedlings outdoors when weather is settled, setting plants 6 to 8 inches apart in loose, fertile soil. To avoid misshapen knobs, take extra care not to disturb the roots while transplanting.
Several times during the long growing season, side-dress with nutrient-rich compost or organic fertilizer. Don’t allow the soil to dry out, yet avoid too much water, which may lead to rot and a browning of the interior. Harvest in the fall before severe frost, using a garden fork to lift the gnarly roots. Shake off the loose soil, snap off the tops, and store alongside potatoes or beets in the root cellar or a cool, dark place until ready to bring into the kitchen for cooking.
Photo: Thomas MacDonald
Say “radish” to an American gardener, and we think of a crimson ball that grows in the early spring, or the ‘French Breakfast’ radish with a scarlet shaft and white tip. Yet for gardeners of Korean or Japanese heritage, the word is more likely to conjure up images of a long, white cylindrical root, known as daikon, a staple in their cuisine. Cooked, pickled, or raw, daikon is a formidable root vegetable that can reach a length of a foot or more and typically weighs a pound at harvest. Giant varieties, such as ‘Sakurajima Mammoth’, are said to reach as much as 100 pounds.
Daikon (Raphanus sativus) is a fast-growing, cool-season crop that is best sown in spring or fall, as it does not like the heat of midsummer. You might think that in order to successfully grow the enormous daikon, you must first start with deeply dug, loose soil. Not so. In fact, the aggressive taproots of daikon, planted densely as a cover crop, are sometimes called on to break up compacted clay.
Mature roots are sweet and juicy, ideal for an Asian radish salad, chopped with yogurt for raita, or sautéed with fish. The green tops are equally useful and highly nutritious in a salad, or braised along with other bitter greens as a side dish or a stuffing for ravioli. And if you are practicing your knife skills, carving the giant daikon radish can result in interesting vegetable art.
How to grow:
Daikons are not demanding when it comes to soil and can tolerate most conditions. For the longest, straightest roots and ease of harvest, work soil deeply or grow in raised beds. Sow seeds 2 inches apart, directly where they are to grow. Thin the seedlings to stand 4 inches apart. Apply mulch between rows to maintain soil moisture and eliminate weed competition.
Daikons are brittle, so take care when lifting them with a fork or spade. Remove the green tops, wash, and refrigerate. Despite their sturdy appearance, daikons do not store as well as other root vegetables, but will keep for up to 8 weeks in the refrigerator or stored in damp sand at about 32°F.
Photo: Thomas MacDonald