Cold Frame Gardening

This is the cold frame on a sunny morning. The lids are open to keep the greens from getting too warm. Most greens like cool weather and will "bolt," or put up seed stalks in hot weather.

The straw bales were put in place last fall to insulate the cold frame through the winter. Despite a bitterly cold winter, spinach planted last September yielded leaves for fresh salad from mid-February on, thanks to the straw bales and heavy snows. Soon these partially-rotted bales will move to the garden as mulch between rows.


Last fall's spinach grew in the front part of this side of the cold frame. The spinach was replaced by arugula seedlings along the right side, and endive and romaine lettuce transplants on the left. I keep a few lettuce and endive seedlings in newspaper pots ready to plug into cold frame vacancies.

Along the back are young buttercrunch and romaine lettuces. They were planted in March while the spinach was still growing. We're eating the thinnings from them.



The right side of the cold frame has three rows of greens – lettuces on the left and right with spinach in the middle. Lettuces on the left grew from seeds I saved from last spring's cold frame lettuce, some of which I let go to seed. Black-seeded Simpson is on the right. The spinach is Bloomsdale, my long-time favorite. Its slightly-savoyed leaves give great texture to a salad.

We eat salad from this section every day. I harvest by thinning. Early salads were made of lots of tiny plants but now just one or two lettuce plants make a generous salad for two. Eventually the remaining lettuces will become heads or thick bunches, depending on the variety. Spinach is harvested leaf by leaf, always removing the oldest leaves. Eventually, depending on temperature, each spinach plant will begin to put up a seed stalk. Spinach leaves become more and more arrow-shaped as the seed stalk forms, as if they were reaching to cast their progeny to the sky.

Also, see later posts on this subject:
March 31, 2011
November 26, 2012
January 22, 2013
April 14, 2013