Using a Cold Frame Greenhouse
For some gardeners, owning a greenhouse is not a possibility due to space or budget constraints. Luckily, there are now a wide variety of smaller greenhouse structures and cold frame greenhouses available to help gardeners extend the growing season. A cold frame greenhouse works best when used from spring to fall to protect plants from the frost. It is best to keep your cold frame ventilated during a warm day, either by opening a sliding door or by propping the structure up (depending on the style), and then close the cold frame once again at night. This enables the plants to get plenty of fresh air during the day, while keeping them warmer at night. By using a cold frame greenhouse, you will be able to start growing earlier in the year and continue growing later into fall. In more mild climates, you can overwinter your favorite plants in cold frames.
There are many styles and sizes of cold frames available. The mini greenhouse is typically designed for patio use, while the a cold frame is generally placed over raised beds. Miniature greenhouses are a great use for container gardening; you simply place pots of your favorite flowers, vegetables or herbs inside. Cold frame greenhouses can also be used in this manner, although it is more common to plant directly into the ground. Your plants in the cold frame are then able to use all the nutrients of the natural soil while still receiving the protection and warmth that the structure provides. If you do plant directly into the ground, be sure to provide about 6" to 12" around each plant to maintain healthy ventilation in your cold frame. Staking your plants and choosing compact varieties will also help so your plants don't outgrow your cold frame. See a cold frame video.