Yes, you can certainly grow a variety of plants in an unheated greenhouse during the winter. The beauty of an unheated greenhouse is that it can provide a safe and relatively warm environment for your plants, without incurring the high energy costs associated with a heated greenhouse. Here are some plants that you can grow in your unheated greenhouse during the winter:
Greens – Lettuce, spinach, chard, and kale are all great choices for an unheated greenhouse. These cold-loving plants are easy to grow, and will produce fresh greens throughout the winter months.
Cold-Tolerant Vegetables – Broccoli, cabbage, and cauliflower are all vegetable crops that can grow well in a cool greenhouse environment. These plants thrive in cooler temperatures, and can produce a bountiful harvest even in the dead of winter.
Warm Season Annuals – If you’re looking to get a jump start on your spring gardening, an unheated greenhouse can be a great place to start warm-season annuals like petunias, impatiens, and geraniums. These plants will appreciate the added warmth of the greenhouse, and will be ready to transplant into your garden once the weather warms up.
Landscape Perennials – Unheated greenhouses can also be used to overwinter hardy landscape perennials. Many plants like coneflowers, daisies, and black-eyed susans can survive the winter in an unheated greenhouse and will emerge in the spring ready to provide beautiful blooms.
Overall, an unheated greenhouse can provide a great opportunity to extend your gardening season, and explore the possibilities of winter gardening. With a bit of creativity and experimentation, you can grow a variety of plants in your unheated greenhouse and enjoy fresh greens and colorful blooms all year long.