As the cooler temperatures of fall arrive, many gardeners start to pack up their tools and call it a year – but not all of them! For those of us who love to grow and harvest fresh produce year-round, a cold frame can be a great solution for extending the growing season. With a bit of planning and preparation, you can even grow crops like carrots and radishes throughout the colder months. In this post, we’ll explore how to set up and manage a cold frame for growing carrots and radishes this winter.
Just click here to read my post on building your own Cold Frame, along with different materials you can use from wood, PVC, blocks or wooden pallets!
Best Type of Carrots and Radishes
Choosing the right variety of carrots and radishes for your cold frame is essential. For carrots, opt for cold-tolerant types such as ‘Nantes‘, ‘Danvers‘, or ‘Paris Market‘. These varieties have a shorter growing season and are known for their ability to withstand cooler temperatures. As for radishes, ‘Cherry Belle‘ and ‘Champion‘ are excellent choices for cold frame growing. They mature fast and can tolerate frost, making them perfect for winter harvesting. Remember, the key to successful winter gardening is choosing crops that are naturally hardy and well-suited to cooler conditions.
Cold Frame Location
Choosing the right location for your cold frame plays a crucial role in ensuring your carrots and radishes thrive during the winter months. Ideally, your cold frame should be situated in a spot that gets at least six hours of direct sunlight each day, even during the shorter winter days. This helps to maximize natural heat from the sun, keeping your crop warm. Position the cold frame facing South to take full advantage of the sun’s path. Avoid areas that are prone to strong winds or waterlogging. A higher ground location is preferable. As this it allows for natural drainage and avoids frost pockets. Remember, the success of your winter garden largely depends on the positioning of your cold frame.
Preparing the Soil
Soil preparation is a crucial step in setting up your winter cold frame garden. Start by clearing the area of any weeds or debris, then dig the soil to a depth of about 12 inches. This loosens the soil, making it easier for the carrot and radish roots to penetrate and grow. For these root vegetables, sandy loam soil is ideal as it drains well and is easy for the roots to push through. Enrich the soil with well-rotted compost or a slow-release organic fertilizer to provide the necessary nutrients for your crops. Remember to maintain a slightly acidic to neutral pH (6.0-7.0) for optimal growth. Lastly, smooth the soil surface with a rake, ensuring its level for even water distribution. Proper soil preparation paves the way for a successful yield of carrots and radishes in your winter cold frame garden.
Planting and Growing Your Carrots and Radishes
After preparing your cold frame and soil, it’s time to move on to planting and growing your carrots and radishes. Begin by sowing the seeds directly into the cold frame, following the spacing instructions on the seed packet. For carrots, a spacing of about 2 inches between seeds is ideal, while radishes need approximately 1 inch. Cover the seeds lightly with soil and water them gently.
Germination should occur within a week or two. After the seedlings have developed their first set of true leaves, thin them out to prevent crowding and ensure healthy growth. Carrots should be thinned to a spacing of about 3 inches while radishes need to be thinned to about 2 inches apart.
Maintaining your cold frame garden involves regular watering and monitoring for pests. Watering should be done in the early morning or late evening to minimize evaporation, and the soil should be kept moist but not waterlogged.
With regards to pests, keep an eye out for common carrot and radish pests like aphids, carrot rust flies, and cutworms. If you notice any pest damage, use organic pest control methods to manage the infestation.
With the right care, you should start seeing your radishes and carrots ready for harvest within a few weeks. Radishes mature faster, usually ready within 24-30 days, while carrots may take up to 60-80 days. As long as you keep your cold frame closed and well-insulated during harsh winter weather, you can enjoy fresh, home-grown carrots and radishes all winter long.
Temperature Regulation
Controlling the temperature within your cold frame is critical for your carrots and radishes’ optimal growth during the colder months. The internal temperature should ideally hover around 32-40°F (0-4.4°C) for best results. On sunny days, even in winter, the temperature inside the cold frame can rise rapidly. To prevent overheating and ensure proper ventilation, it’s important to open the cold frame during the day and close it at night when the temperatures drop. You can use a thermometer to monitor the temperature and adjust accordingly.
To monitor your temps, consider investing in a max-min thermometer. This tool will help you monitor the coldest and warmest temperatures in your cold frame each day, allowing you to make necessary adjustments. There are also bluetooth thermometer/hygrometers so you can monitor with your phone.
In extremely cold weather, you can add insulation to your cold frame. Straw bales or old blankets can be placed around the frame to provide additional heat retention. Remember, the goal is to create a stable environment that will protect your crops from frost, while still providing them with the necessary light and heat they need to grow. By effectively regulating the temperature within your cold frame, you can ensure a productive yield of carrots and radishes even in the heart of winter.
Happy Gardening!
With a bit of patience and TLC, growing carrots and radishes in a cold frame can be a fun and rewarding way to keep your garden going all year long. Remember to choose the right location, prepare the soil properly, and sow your seeds mindfully. Monitor the temperature and humidity levels inside your cold frame, and be prepared to adjust as needed. And most importantly, enjoy the delicious bounty of fresh, homegrown produce throughout the winter months!
Please be sure to check out my Gardening Blog Post page for more growing tips on Coldframe gardening, Indoor Bulb Gardening, Hydroponic Gardening, Container Gardening, Mums, Herbs, African Violets, planting Bulbs, Flower Gardening, Vegetable and Fruit Gardening, Indoor Houseplants of all kinds, Cactus, Succulents, Hanging plants, Deer resistant plants and even Bird, Bee, Butterfly and Hummingbird Gardens!