Plant greens bred for cool weather
The author sets out transplants or sows seeds in the fall.
Lettuce is naturally a cool-season crop and, because of its popularity, many varieties have been bred to withstand very cold temperatures. Those that are suited to cold weather are easy to identify by names like ‘Arctic King’ and ‘North Pole’, two green butterhead-type lettuces. There is also ‘Winter Density’, one of my favorite romaine lettuces, which has been known to last almost year-round in the mountains of Vermont. I also grow ‘Winter Marvel’, a green loose-leaf lettuce that is extra cold hardy, and ‘Rouge d’Hiver’, a loose-headed romaine type with a slight red blush. Two more of my favorites are ‘Continuity Red’, a red crisphead lettuce, and the romaine-butterhead cross ‘Blushed Butter Cos’.
In addition to lettuce, I grow other cool-season greens. Kale, especially the variety ‘Winterbor’, is one of the hardiest winter greens and is by far the best performer in my winter garden. I also grow the tasty and nutritious miner’s lettuce (Claytonia perfoliata) and corn salad (Valerianella locusta), also known as mâche or lamb’s lettuce, both of which will overwinter into spring. My winter garden is never without arugula (Eruca sativa), which is at least as tough as the cool-season lettuces, and mizuna (Brassica juncea). French sorrel (Rumex scutatus) is another hardy winter green that will survive in pickable form with no more than a few fall leaves packed loosely around its roots. A smooth-leaf spinach, such as ‘Denali’, and both curly-leaf and Italian flat-leaf parsley grow contentedly under my row cover all winter.
I direct-sow the seeds for my salad plants (or plant seedlings) in September in my Zone 7 garden. Those who live in warmer or cooler areas should time planting so that the young greens can become well established before the weather cools off. If you start the plants when the weather and soil are already cold, you will have a tougher time getting them to produce for you. I don’t do anything special to the soil except to scratch in some well-rotted compost before sowing or planting to encourage good root development. The greens will need about half the amount of water they use in the summer, and they can typically get this from rain, which penetrates the row cover fabric. I also use drip irrigation to make any additional watering easier.