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Cold Frames  For Season Extension

Cold Frames image

Cold frames act as mini-greenhouses that fit on top of our raised beds or can be placed directly on the ground. During winter months, cold frames trap heat from the sun to maintain an environment that is up to 30 degrees warmer than outside. With cold frame technology, you can extend the growing season into the late fall and early spring, with potential to harvest year round.

Our cold frame technology utilizes a heat-activated automatic venting arm that opens and closes the lid to regulate fluctuating temperatures. This is critical to promote healthy growth and keep plants alive in the spring and fall, allowing for the highest possible success rate without constant monitoring.

Extend the Growing Season up to Three Months

A typical growing season in Massachusetts lasts from mid-April to mid-October, or last frost to first frost. Cold frames generally extend the season from the first week of March through to the first week of December, about three months. Many crops can over-winter for an early harvest in March. And in mild winters, there’s the possibility of year round harvesting.

  • Install the beginning of October to extend the fall season (remove pest fencing and trellising before installing cold frames)
  • Install the first week of March for an early spring start date
  • Over-winter in cold frames December through February, with the possibility of year round harvesting (weather permitting)

Cold Frames

Each cold frame is built to order, to cover half or all of our 4′ x 8′ raised beds. For more information on availability, please call us at 617.776.1400 or email.

Cold Frame Crops

Plants that can be harvested into the late fall with a cold frame:

  • greens: lettuces, kale, collards, chard, and spinach
  • broccoli
  • hardy herbs
  • carrots
  • beets
  • radishes

Plants that can be seeded in late fall for overwintering with a cold frame:

  • beets
  • carrots
  • kale
  • spinach
  • scallions
  • hardy winter greens: claytonia, mache, and sorrel