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Extend Your Growing Season with Cold Frame Gardening

Extend Your Growing Season with Cold Frame Gardening

 

Cold frame gardening is an excellent way to extend your growing season and protect tender plants from harsh weather. Start seeds earlier in the spring and continue growing well into the fall or even winter, depending on your climate. Cold frames are perfect for hardening off seedlings and growing cold-hardy vegetables like lettuce, spinach, and kale. Follow our tips below to get started.

Select a Location

The first step to success is selecting the right location for your cold frame. Choose a spot that receives ample sunlight during the shorter days of fall and winter. South-facing locations are best to maximize sun exposure. Ensure the area has good drainage and consider positioning your cold frame against a wall or fence for added wind protection and thermal mass. 

Build It

Putting a cold frame together is an easy afternoon project for the DIY inclined. Supplies cost between $40-$60 and take only a few hours to construct. Cold frames are also a great way to use up spare material that’s hanging around the garage. Here are a couple of step-by-step plans from our friends at The Home Depot and Joe Gardener. 

Temperature Control

Monitor the temperature inside your cold frame closely, as it can heat up quickly on sunny days. Ventilation is crucial to prevent overheating, so be prepared to prop open the lid or use automatic vent openers. Insulate the sides of your cold frame with straw bales or bubble wrap to retain heat during cold nights. Consider using thermal mass, such as water-filled containers or dark-colored stones, to absorb heat during the day and release it at night. On extremely cold nights row covers or a soil heating cable can help provide an extra layer of protection. 

Maintenance

Regularly clean the glass or plastic covering for maximum light transmission. Monitor soil moisture carefully, as cold frames can dry out quickly in sunny weather. Reduce the risk of fungal diseases by watering in the morning so excess moisture evaporates. Remember to rotate your crops and practice good sanitation to prevent pest and disease buildup.