The first collards I ever saw were some three-foot-tall plants in a San Francisco backyard; the first kale I ever enjoyed eating was grown by some back-to-the-land farmers in western Oregon. Since I moved to North Carolina, I've taken up the southerner's dedication to growing and eating collards with real enthusiasm. These two brassicas can be grown anywhere in the country at some time of the year because they are the least fussy plants in the large cabbage tribe. Their prime value to gardeners is that these highly nutritious greens thrive and are most delicious when it's too cold for other vegetables.
Don't let their dissimilar looks fool you: Collards and kale are very closely related. In fact, collards are really a type of kale, a primitive member of the cabbage family. Kale is similar to the wild headless cabbage that grows on the seacoasts of western Europe and the Mediterranean. This botanical trivia helps to explain why collards and kale can be grown, harvested and cooked in much the same way.
There are a surprising number of collard and kale varieties. In its Garden Seed Inventory, The Seed Savers Exchange (an organization devoted to preserving open-pollinated seeds) lists 41 kales and 10 collards offered by American seed companies in the mid 1990s. The name Vates crops up in names of both kale and collards, and I figured Dr. Vates for some distinguished plant breeder. But Vates turns out to be an acronym for the Virginia Truck Experiment Station, a hotbed of collard and kale research from 1909 through the 1960s.
The most common kale in America today is frilly and blue-green 'Dwarf Blue Curled Scotch Vates'. Slow-bolting 'Squire' is an improved Vates type. Tightly curled varieties like these are favorites of commercial growers raising the "garnish kale" that is challenging parsley as the restaurant garnish of choice. But other culinary kales are frilly in the extreme and blushed with red 'Ragged Jack', 'Russian Red', and 'Winter Red'. These presage the outrageous ornamental types that have proliferated in the hands of Japanese plant breeders. And there are varieties with large, flat, strap-like leaves ('Lacinato', 'Smooth Long Standing') that point the way to collards, which themselves show aspirations toward the cabbage form.
Collards fall into two groups. 'Vates' and 'Georgia' collards are popular and typical of the loose-leaf type. The leaves are dark green and arise from a stalk that elongates slightly as the plant grows (as do most kales). 'Champion' is a slow-bolting variety selected by the VA Truck Experiment Station. The other varieties spread wide but stay more compact, eventually forming a loose head of paler green leaves in the center. 'Morris Heading' and 'Cabbage Collards' are the best-known loose-heading varieties.
Hybrid collards are prolific, grow quickly in cool weather and mature all at once. 'Flash' and 'Heavi-Crop' are Vates-type hybrids; 'Top Bunch' is a Morris-Heading-style hybrid. But for gardeners plants mature at different rates are more practical.
'Green Glaze', an old collard variety, has dark, shiny leaves that seem to be less attractive to caterpillars. Brassica breeders are attempting to introduce this genetic trait into broccoli and the other more glamorous relatives of collards.
Both of these hardy greens grow best in cool weather and rich soil, with plenty of moisture. In general, sow seeds 1/2 inch deep six weeks before you want to plant them in the garden. Space plants two to 2 1/2 feet apart and feed lightly. Mulch helps to keep soil cool and moist.
Kale and collards can survive winter temperatures as low as 5° to 10° F if they are gradually acclimatized, but sudden cold snaps can be deadly. Kale is somewhat more cold hardy, and collards are a little more heat tolerant.
In cooler regions, plant either in spring for a midsummer crop or anytime up to midsummer for harvest in fall to early winter. Says Rob Johnston of Johnny's Selected Seeds in Albion, Maine, "We plant kale from late June to late July and eat it until Christmas." They could follow the same schedule with collards, too.
In the South, late summer is the best time to plant. Here in North Carolina, I should start seed in August, but I tend to forget during the dog days. So I often buy my plants in early fall. I've had success using polyester row covers, which will keep kale and collards growing much later into the fall, plus keep pests away. We eat the greens into winter, and, in a good year, until March when they bolt into flower.
Thelma Reaves is a veteran gardener in Ayden, the home of the North Carolina Collard Festival held every September. Collards are prominent in her three- to four-acre market garden. She's nearer the ocean and her climate is milder than mine, so she has a slightly different schedule. "In October I start seed outdoors in a protected spot, then transplant to the field in January," she says. By March she is selling greens from plants that keep cropping straight through summer and fall into the following spring when they finally bloom. But in hot, dry weather, "collards just aren't fit to eat," says Thelma.
Her method of fall-seeding collards for midwinter transplants can be tricky. If the plants are too small, they won't survive the cold. If too large, they flower prematurely in spring, a condition called vernalization. According to Doug Sanders, North Carolina State University Extension horticulturist, plants with more than six to eight leaves will vernalize. The area where spring collards may be fall-planted, says Sanders, stretches up the coast into New Jersey--about USDA Zone 7.
Collards and kale offer many pickings of fresh greens at a time of year when there's littl else to harvest. Folks often say collards are sweeter after the first frost, but an actual 32oF frost isn't crucial. Cool weather is enough. Doug Sanders has an explanation: "Cool weather changes starches in the leaves to sugars, and also changes the structure of protein flavor compounds."
The southern way to harvest is to break off the larger leaves, but not the lowest ones, which tend to be tough, dirty and somewhat yellowed. The rest of the plant continues to make more leaves for subsequent harvests. If the plants are threatening to bolt, I'll cut the whole plant--or sometimes use the unopened flower buds for an early spring version of broccoli. If I want a few leaves to chop into a winter salad, I take the tenderest few from the top.
In Thelma Reaves's neighborhood, they begin to cut the whole central head of the cabbage-collard types when serious cold weather is expected, traditionally around Thanksgiving. "That central head is lighter green, sweeter and very delicious," says Thelma. Central heads are the main collard crop December through February in Ayden, whereas just the leaves are picked spring through late fall, according to Thelma.
On older collard leaves and in warmer weather, the central midribs may be tough and are often cut out of the leaves before cooking. In fall when I'm cutting my collards, the midribs are very sweet and I chop them up with the rest of the leaves.
Collards and kale are a nutritionist's delight. A cup of cooked collards contains only 55 calories but twice the total recommended daily dietary allowance for vitamins C and A. That cup contains more calcium than a cup of milk, and more potassium than a banana. Kale is a bit lower than collards in these nutrients, but higher in iron.
Traditional greens cookery could go on for hours and include fatback or bacon. But to me, collards and kale are best with minimal cooking--just long enough that they are tender but still a nice green color. Our favorite way to eat these greens is sauteed with garlic, onion and tarragon, seasoned with a few shakes of vinegar and tossed with pasta and grated cheese. This very un-southern use of collards and kale is consumed enthusiastically by all members of my family, whether age 1 1/2, five or over 40. Not bad for something that grows so easily and satisfies the voice of dietary conscience.
You may not have noticed but there's something of a boom underway in the ornamental kale trade. These shockingly colorful kales are extremely useful during fall and early winter to landscapers in large gardens, who must please a public gone numb on mums and pansies. At Disneyland and Disney World they are planted by the thousands. Even more--hundreds of acres' worth--are used in restaurants across the country, where they serve as garnishes or as an edible underlay on lavish salad platters.
These new varieties come mostly from Japan and are called "ha-botan," or leaf peonies. The hybrid uniformity in size, color and rate of growth of these ornamental bedding plants is a distinct plus for both gardeners and commercial growers.
There are three distinct leaf types: crinkle-edged like kale, such as 'Nogoya Hybrid'; feather-leaved, like 'Red Peacock'; and round-leaved, such as 'Tokyo Hybrid', which looks something like a collard or cabbage and may even be listed as "ornamental cabbage." Each kind comes with centers of red, pink or creamy white. The usual practice is to plant at least two types for contrast.
To grow any of the ornamental kales to perfection, timing needs to be precise. Coloration doesn't begin until night temperatures regularly drop below 60oF, and full coloration takes three to four weeks. The plants need to be almost full grown when coloring time arrives. Here are some guidelines for achieving that:
Deborah Wechsler is a freelance writer and consultant based in Pittsboro, North Carolina.
Photography by National Gardening Association
Article published on June 23, 2008.