Extending the Garden Season: Frost Protection
Not ready for frost and cold weather to wipe out your garden and other plants? Me neither, especially when we are having such a mild Fall! Typically in September and October, the weather can get very unpredictable here in Minnesota. We can experience our first frost by mid-September to early October. The actual first frost date in Minneapolis is around October 5. The first step in frost protection is knowing your first frost date! To find the frost date in your location, go to the National Weather Service, Old Farmer’s Almanac or other sites to check the first frost date.
Frost is destructive and will kill your plants. According to the Old Farmer’s Almanac, frosts are classified in three categories (all temperatures in Fahrenheit):
- Light freeze: 29° to 32°— tender plants killed.
- Moderate freeze: 25° to 28°— widely destructive to most vegetation.
- Severe freeze: 24° and colder—heavy damage to most plants.
The key to garden frost protection is getting your plants covered before the cold strikes, which is typically in the early morning hours. You can use old sheets, blankets and towels to cover your plants, just make sure to remove them in the morning.CAUTION: Try not to use plastic tarps or sheeting! Use it only if you make a tent over the plants (plastic should not touch the plants). Since cold air is dense, it will freeze moisture that is trapped by the plastic tarp or sheeting.
As you can see in the picture above and the video below, I did use plastic tarps and bed sheets because that was all I had available. As you can see, I did have some frost damage on plants that did not make it under the plastic tarps and bed sheets. I did not have any frost damage for plants under the plastic tarps and bed sheets. It was worth the gamble (and it worked)! I am still growing tomatoes in November thanks to this frost protection and a mild Fall!
I created a video showing my frost protect, and you can watch it below. In case you want to see frost protection up north in Wisconsin and frost damage in my garden in 2014, check out these Small Scale Gardening videos: