Thursday, May 17, 2012
Summertime is much more challenging for growing greens. Most “bolt” when temps start hitting the upper 70’s and 80’s.
Greens that have bolted are still edible, but most become bitter tasting.
Tricks to keep greens growing all summer is shade, progressive sowing, perennial greens, early morning harvesting and choosing varieties that are resistant to bolting in warm weather.
For shade, there are options. You can grow your greens in pots and move them to the East or North side of the house. You can cover them with a sun cloth. Or you can plant them behind or amongst taller summer veggies. You can also plant in a micro climate that provides cooler temperatures, say against a wall that is shaded most of the day. Greens do need sunlight, but in the summer, there is good light reflected so 6 hours of direct sunlight is not a necessity.
For lettuce, it is critical to do progressive sowings. The typical recommendation is every 2 weeks. I actually resow about once a month. The difference is because I take the outer leaves from the lettuce we grow so the plants produce over a longer period of time without bolting. If you want to harvest full heads, then every 2 weeks is the advice to follow.
Perennial greens will continue to produce all summer. Chard, sorrel, New Zealand spinach, arugula, salad burnet, French or American dandelion (French dandelion has been cultivated specifically for salad greens so its leaves are much larger than the American dandelion, but both are good for eating!) radicchio, and chives are great for salads. Pick the youngest leaves for salads and use the more mature leaves of chard, radicchio and sorrel for cooked greens. Picking right after a rain or first thing in the morning also gives the sweetest leaves.
I keep my greens separated into 3 categories-those for spring/fall, those for winter and those for summer harvests. Any do great for spring/fall. Winter and summer greens have a much narrower field of suitable candidates.
Summer candidates I am growing this year:
*Spinach-Summer Perfection, New Zealand Spinach (not a true spinach but has a spinach like flavor)
*Lettuce-Nevada Summer Crisp, Red Sails, Rouge d’Hiver, Freckles Romaine, Summertime Crisphead, Tomahawk, Loma French Crisp
*Red Leaf Amaranth
Nevada Summer Crisp Lettuce does very well in hot temp’s. I have been growing summer crisp for a few years now. It volunteers itself all around the garden. It is a pretty, ruffled lime green lettuce.