When it comes to using a cold frame in your garden, it’s important to know the temperature limits that your winter crops can tolerate. While most winter crops can handle a bit of frost, they won’t be able to grow when the temperature drops below 40 degrees Fahrenheit. This means that if you want your plants to thrive, it’s crucial to keep the cover of your cold frame on anytime the weather is below 50 degrees Fahrenheit.
I remember one winter when I didn’t pay enough attention to the temperature and left my cold frame uncovered during a particularly cold night. The next morning, I was devastated to find that my plants had been damaged by the freezing temperatures. It was a tough lesson to learn, but it emphasized the importance of monitoring the temperature and providing adequate protection for my winter crops.
Cold frames are designed to create a microclimate that is warmer than the outside temperature, which helps to extend the growing season. However, they are not capable of generating heat on their own. Instead, they rely on the sun’s rays to warm up the interior. This means that if the weather is too cold, even with the cover on, the temperature inside the cold frame may not be high enough for your plants to thrive.
In my experience, I have found that cool weather crops, such as lettuce, spinach, and kale, tend to be more sensitive to extreme cold temperatures. They prefer temperatures between 50 and 70 degrees Fahrenheit for optimal growth. When the temperature drops below 40 degrees Fahrenheit, these crops may struggle to grow and may even become damaged or die.
On the other hand, there are some winter crops, like carrots, beets, and cabbage, that are a bit more tolerant of cold temperatures. They can handle temperatures as low as 20 degrees Fahrenheit, but it’s still important to provide them with some protection, such as a cold frame, during extremely cold weather.
It’s worth noting that the specific temperature limits for your winter crops may vary depending on the variety and the stage of growth. Some varieties may be more cold-hardy than others, and younger plants may be more susceptible to cold damage than more established ones.
The temperature that is considered “too cold” for a cold frame depends on the specific winter crops you are growing. Generally, if the temperature drops below 40 degrees Fahrenheit, it’s too cold for most winter crops to grow. However, it’s always best to monitor the temperature and provide extra protection, such as a cover for your cold frame, during extremely cold weather.
