Do you know what a cool season crop is?
Cool season crops are plants that have adapted to cool climates. These kinds of plants have adapted to temperatures that are below 70 degrees. Some even like temperatures below freezing.
Cool season varieties are best harvested in cooler temperatures of spring or fall (or winter for our mild climates gardeners). The temperature is important because heat can encourage bolting (prematurely flower), which causes bitterness in crops like lettuce and cilantro. Other crops, like broccoli or cabbage, may fail to produce a harvestable crown or head if temperatures are consistently warm, and they aren’t able to mature in cooler temperatures. For crops such as Brussels sprouts, some cabbages, and parsnips, this can mean sowing while it’s warm, so plants will grow in the heat but mature in the cool season. Botanical Interests offers many heat-tolerant and bolt-resistant cool season crops, making home gardening more successful!
Here in Annapolis, as early as March you can start planting cool season crops. The Maryland Extension Service publishes a list that tells you when it's safe to plant whatever vegetable you'd like to plant. You can access that list here.
Just this past weekend, I went outside and was pruning my rose bushes. My assistant went out and planted peas from seed, and she figured that even if we get a surprise snow storm in March, she can just bring them inside!
Fun Fact: Many plants, including cool season varieties, are able to convert starch into sugar, which lowers their freezing point. This “sweet” conversion not only protects plants from frost, but also can make for a literally sweeter harvest.
Thanks Homestead Garden Center for such great information!