Kale’s culinary star has certainly enjoyed a recent rise. For a long time this basic brassica was a humble, overcooked, nutrient-rich winter green. But now it has become a salad, a crispy chip, and even a baby green.
It features on the plates of vaunted establishments like Seattle’s iconic Canlis where it serves as a support to the grilled swordfish, but it is equally at home at Tom Douglas’s pizza joint Serious Pie—where it is delivered fresh with parmesan, chilies, and pine nuts in a tangy, spicy vinaigrette.
Now it’s time to look beyond the kale to a whole world of winter greens. WSU researchers and students are testing a variety of crops for taste, yield, and hardiness with the hopes that Washington farmers can reclaim more of the vegetable market in wintertime, when so much of our plates depend on crudités from California.
On the farm at the WSU Mount Vernon research station, master’s student Charlene Grahn ventures into the cold November morning to check on her trial of Salanova cultivars, little multi-leafed lettuces that she’s testing for over-winter suitability in the Puget Sound region. “These went in back at Halloween,” says the horticulture student, bending to gently press down on the soil near a plant. Two rows of tiny red and green jewels span from where she stands to the end of the hoop house.
Grahn is examining eight types of Salanova: four leaf shapes (butter and oak among them) and each shape in red and green. She started the plants in the greenhouse. Germination in the cold soil outside would have taken too long, she explains. And now that they’re in, they still have a few months before being ready for harvest. Plants like these don’t grow much in December and January, but come February and the warmer, longer days, they’ll invigorate, expand, and be ready for picking by March.
Salanova, introduced by a Dutch seed breeding company in 2007, is a high yielding small lettuce. Each head has about 200 leaves, with crisp character and twice the shelf life of traditional baby leaf lettuces. The leaves grow densely from a central core, making it easy to harvest, explains Grahn. And once it’s cored, the uniform leaves easily fall free.
Cold snaps in November and early December didn’t much hurt the lettuces in Grahn’s trial. “They’re pretty frost tolerant as long as they’re hardened off,” she says. She did this by gradually bringing them out of the greenhouse, first during the warm mid-day and then increasing their time and exposure to the outside.
“They’ll be fine as long as we keep the beating rain off of them,” says her professor Carol Miles.
While the lettuces are attention-worthy, many other winter crops are worth exploring, says Miles. Bok choi, pok choi, and cabbage all have a waxy leaf coat that helps them through the cold. To this list, Miles adds mizuna, chard, chicory, broccoli, mustard greens, and leeks. “Leeks are a fantastic winter crop,” says Miles. “They can be outside with no protection, nothing. It’s a beautiful crop.”
Farmers in Port Townsend performed some joint chicory trials with the Organic Seed Alliance and WSU Extension, finding that the plant did quite well, even in the rainy area of Chimacum. The plant, also known as French or curly endive, has a bitter leaf that mellows as it cooks. It features in several Mediterranean cuisines. Altura in Seattle has picked up on that, producing a popular chicory salad by pairing it with gorgonzola, hazelnuts, and apples.
Because winter plants take longer to reach maturity, they may be a little more bitter, just slightly more tough. But that simply gives chefs slightly different flavors and textures to explore.
Growing winter greens involves a different mindset, says Miles. Water is your biggest problem because it spreads disease which causes rot. But it’s easy enough to keep the plants covered. And “the key to freezing is that you don’t touch your crops until they thaw out,” says Miles. “In the summer, we like to harvest in the cool morning. But in late winter and early spring, it’s better to wait until at least 11 or 12.”
While growing winter greens in Eastern Washington almost certainly requires a greenhouse, WSU has a few lettuce trials under glass in Pullman. “That’s kind of our project, to replace some of the imported greens,” says Miles.
In 2012 Binda Colebrook updated her guide Winter Gardening in the Maritime Northwest and added to a long list of produce including fennel, salsify, and arugula, suitable for cold season cultivation. Before World War II, she notes, most serious Northwest gardeners knew that certain vegetable varieties could overwinter. But then came the war and then mass transportation, which brought a bounty of produce from the south to upstage the local offerings.
In the 1970s, Colebrook worked with a handful of gardeners around the Puget Sound region to unearth old and new cold-hardy varieties. “We were just a group of gardeners encouraging each other to be less dependent on trucked in vegetables,” she wrote. Together they discovered the “excitement of homegrown lettuce in January.”