Sue Hartman, Garden Hotline, Seattle Tilth
There’s plenty to get excited about when it comes to leafy green vegetables. Besides packing major nutrition into their leaves, greens are one of the most productive crops in the short growing season of the Pacific Northwest since leaves are the first harvestable part of the plant. It takes much less energy for a plant to produce leaves than fruit, seeds or roots. Greens are often resilient and long-lived. Some can even tolerate hard frosts!
Greens tolerate shade better than other crops if they are grown just for leaves. Chard, kale and collards can grow for much longer than many vegetables. If planted early, these greens may become strong enough to survive the summer heat and winter frosts until the following spring when they finally send up flowers and call it quits. Brassica flowers — arugula, mustards, kale and collards, to name a few — are all edible, so the plant won’t go to waste if they bolt (send up flower stalks and taste bitter) early! Short, tender greens — such as lettuce and spinach — will grow better in the spring or fall, as they tend to bolt when the weather heats up. Keep in mind that arugula, mustards and Asian greens can have a very fast life cycle; they grow quickly, flower and are done, so no need to pull too many hairs over them.
Leafy greens are vital in cuisines around the globe. They are packed with nutritious fiber, vitamins, minerals and antioxidants, especially vitamins A and C, calcium, iron and folate. Contrary to fast food culture, lettuce isn’t the only leafy green out there. Plenty of leafy green nutrition goldmines are readily available on the supermarket shelf: Swiss chard, spinach, cabbage, arugula, mustards, kale, collards and many others. Even less common leafy greens are corn salad (high in many B vitamins and omega-3s), miner’s lettuce (high in vitamin C and iron) and minutina (medicinal properties). Beets and turnips can also be grown just for the tops. Don’t forget broccoli leaves. They are edible and are just as nutritious (or possibly even more so) than the florets!
Be Young and Juicy
For those short on space, greens are easy to grow in containers. “Microgreens” is a term for extra-juvenile vegetables. This could include spinach, beets, chard, lettuce, mustards and even peas that have grown in soil for at least 7 days. Keep them going a little while longer for a pot full of gourmet baby greens! Micro and baby greens grow plentifully in containers. No need to thin; just harvest when needed. If larger leaf greens are needed, thin them out and give them some space. Lettuce has shallow roots, so plant it in a wide and shallow container. Kale, collards and chard will get much larger and will need larger and deeper containers.
How to Care for Your Greens
Leafy growth needs nitrogen to thrive. Liquid fertilizers that have a higher first number (5-1-1) are a good way to deliver a quick power boost to leafy greens and are an easy way to feed plants grown in containers. Seedlings planted in the ground early in the spring when the soil is still cool will also benefit from a dose of liquid fertilizer, or amend the soil before planting with organic sources of nitrogen, such as meals (alfalfa, cottonseed, fish and feather meal), manures and worm castings. The plants will be able to break the ingredients down to use as food later on when the soil warms.
To learn more about growing leafy greens or any other edible or ornamental crop, contact the Garden Hotline at 206.633.0224 or gardenhotline.org. Take a class with Seattle Tilth or purchase a copy of our newly revised Maritime Northwest Garden Guide. We’re also on Facebook, Twitter and YouTube.
Pictures and article courtesy of Seattle Tilth