How to Grow Kale and Which Varieties to Choose – The New York Times

Supported by
When it comes to kale, the organic farmers at Adaptive Seeds have a few things to teach you — and some versions of the familiar green that may not be so familiar.
Send any friend a story
As a subscriber, you have 10 gift articles to give each month. Anyone can read what you share.

Yes, Sarah Kleeger knows: Kale is not exactly making headlines these days. Not anymore.
“Kale is so 2010, or whenever,” she was saying the other day by phone, from Sweet Home, Ore., as she walked through her kitchen garden, describing and sampling this green and that, a sort of virtual show-and-tell and tasting.
Lest she be misunderstood, though, she quickly added: “But I’m definitely not bored with kale, and still celebrate it.”
No matter how familiar or even generic kale has become, Ms. Kleeger would not be without it. It is an essential at her home, and among the nearly 600 vegetables, grains, herbs and flowers in the Adaptive Seeds catalog that she founded in 2009 with her partner, Andrew Still.
A depth of kale genetics remains a signature feature of their certified organic farm and seed operation. This year’s availability list includes 14 types — one of which, Kale Coalition, is a diverse gene-pool mix of 17 kales and their crosses.
It has been 15 years since the pair, who were then working on other people’s organic vegetable farms and had the winter off, took a four-month, seed-focused trip to nine Northern European countries. That region’s climate translates well to the one at home, and to other North American areas, so they knew that any seed they acquired would be at least partly adapted to big portions of the country.
“We’re seed nerds, so we took our life savings to Europe to look for seed,” Ms. Kleeger told me when we first met, almost 10 years ago. They also brought along seeds to share.
If they were not already kale nerds, too, when they embarked on what they called their Seed Ambassadors Project, they were when they got back. The trove they returned with — some 800 varieties of vegetables that weren’t commercially available in the United States at the time — included close to 20 kales that weren’t the same-old, same-old supermarket model of the day.
The ambassadors of seed became connoisseurs of kale, and are ever at the ready with advice on how to achieve a year-round harvest and which variety is best suited to which culinary purpose. For not all kales are created equal.
It is just one of various passions for the couple, who likewise have a thing for Northern-adapted tomatoes (they have more than 100 kinds), peppers and beans (snap and dry, fava and runners). Oh, and corn — including flint types for grinding into meal.
“Since we learned how to make pozole out of our homegrown corn, we’ve become even more enamored with corn as one of our favorite crops,” Ms. Kleeger said.
Lately, Mr. Still and Ms. Kleeger also find themselves with a growing collection of edible ornamentals — or what they call “edimentals” — including amaranth and quinoa, which are as beautiful as they are tasty. And not just for their heads of grain, but also for their leaves.
The catalog features other unusual greens, too, some of which were offering tasty samples on a recent March day.
“From a gardener’s perspective, I have really come to appreciate some of the perennial ones, in particular,” said Ms. Kleeger, naming some names.
No garden, for example, should be without a patch of sorrel (Rumex acetosa). Its lemony foliage is a welcome accent green in spring salads, and even winter ones. (It bolts, then mostly rests in summer heat before producing again in fall.) And it is the mainstay of unforgettable sorrel soup.
Adaptive’s sorrel, like so many of their seeds, has a story: On the Seed Ambassadors trip, Mr. Still and Ms. Kleeger visited a farmers’ market in Transylvania, where an older Hungarian man was selling seed in packets he had fashioned out of newspaper. Their friend, who was acting as a translator, didn’t speak Hungarian, so the sorrel’s provenance before that point is sketchy. Mr. Still and Ms. Kleeger simply called it Transylvanian Sorrel. Back home, it has been growing steadily, spreading in a well-behaved way.
And here’s something even less familiar: What about a perennial green with a cucumber flavor that doubles as a handsome ground cover? Salad burnet (Sanguisorba minor) — which is great in salads, as its name suggests — checks both boxes.
Sculpit or bladder campion (Silene vulgaris) is a short-lived perennial that adds an herbal flavor hinting at arugula or chicory to salad, risotto or an omelet.
Alexanders (Smyrnium olusatrum) “is halfway between lovage and celery in appearance,” Ms. Kleeger said, “and halfway between an herb and a green in use.” A biennial or short-lived perennial, it tastes like mild parsley.
For celery flavor without the thick stems, ideal for mirepoix or flavoring soups, grow Hollow Pipe of Malines (Apium graveolens), a Belgian heirloom cutting celery.
And while one crop or another is sometimes referred to as “the next kale” — the annual orach or mountain spinach (Atriplex hortensis), for instance — the Adaptive farmers appreciate each one for its individuality and performance, not for the hype. What’s not to love about the pure magenta deliciousness of their Red Flash orach, with its heart-shaped leaves?
Another annual that’s good for salads, the walnut-flavored Doucette d’Alger (Fedia cornucopiae), grows like mache, but faster and larger. And there’s a bonus, Ms. Kleeger pointed out: It covers itself in purple flowers that pollinators like.
Kale is a biennial whose sweetness is brought out by cold weather, and it will overwinter in many places. Seed shoppers may see one of two Brassica species listed in Latin beneath a variety’s description.
Those classified as Brassica oleracea, or European kale, are probably the most familiar, but there are distinctive varieties among them. The English heirloom Madeley, with extra-large leaves and robust yields, is one. The popular lacinato types, sometimes called Tuscan or dinosaur kale, are in this species, and Adaptive’s version is no typical dark-green suspect: Dazzling Blue Lacinato is extra colorful, with blue-green leaves and vivid purple stems and midribs.
But it is the extra-tender, milder-tasting leaves of the Brassica napus kales — the Russo-Siberian ones, mostly from Northern Europe and Northern Asia — that Mr. Still calls “the best of the best.” Red Russian and Siberian are the two best known to gardeners.
Napus types are especially good for salads. Highly recommended: Simone Broadleaf, developed in collaboration with the Culinary Breeding Network and Timothy Wastell, an Oregon-based chef. The B. napus kales are also the hardiest, surviving to at least 10 degrees, and the Western Front variety is especially so.
And some are positively frilly: North Star Polaris, for instance, or Russian Frills. And for the ultimate in froth, try Bear Necessities, which has been called the seaweed of kale.
“It certainly gives a salad a lot of loft,” Ms. Kleeger said.
Kale, she is quick to point out, is not a summer vegetable: “You can eat it year-round if you manage your rotations, though some times of year it’s way better.”
In their kitchen garden, she and Mr. Still sow two rotations: one in early spring, to take them through midsummer, and another in mid-July. “Our fall crop is here to eat from through to spring,” Ms. Kleeger said, “in the great refrigerator of winter.”
Kale can be direct-sown, but to get ahead of weed competition, Ms. Kleeger and Mr. Still start seeds in the greenhouse in early March, where they grow for about five weeks, before transplanting them into the garden in early April. That’s a month or so ahead of their mid-May average final frost date, but the soil has warmed sufficiently and the days are long enough to urge rapid growth.
The July sowing is transplanted out in August; this is the crop that will be harvested for seed the following year, in June or July.
They space the kale seedlings 12 inches apart in all directions, and at spring planting time they enrich the bed with a 4-4-4 organic fertilizer blend or chicken-manure compost.
Tighter spacing is fine if you plan to thin the plants as they grow, harvesting some along the way. Beginning in June, Ms. Kleeger may harvest a couple of leaves from each of her half-dozen spring-sown kitchen garden plants every week.
“It’s good to keep harvesting gradually like that, when they’re tender,” she said, “and not to leave them sitting on the plant very long after they reach full size.”
In her first farming season, before she knew kale so well, Ms. Kleeger recalls seeing the biennial plants start budding up about this time of year, going into flowering mode beginning in March.
“Oh, it’s bolting — it’s done,” she remembers thinking. “But from my farming mentors, I learned otherwise.”
What is called the raab — asparagus-like shoots bearing flower buds — was beginning to form. Harvest when the buds are tight and look like miniature broccoli flowers, before they stretch, and it can be eaten raw or cooked the way you would broccoli.
“Pretty soon, I saw people start selling it at farmers’ markets,” she recalled.
Any brassica will do this if you leave it long enough, she learned. Now she looks forward to cabbage raab, too, and the “amazing delicacy” of collard’s version.
As she put it, “It’s a celebration of things as they go to flower.”
Not a bad way to start a new season in the garden, and on the farm.
Margaret Roach is the creator of the website and podcast A Way to Garden, and a book of the same name.
For weekly email updates on residential real estate news, sign up here. Follow us on Twitter: @nytrealestate.