Kale doesn't mind frost. In fact, the leaves taste sweeter after a frost has hit them.
There are many plants that don’t mind frost and other plants that continue to thrive for several months longer if they receive some type of frost protection. Kale, for example, doesn’t mind frost – and will thrive outdoors throughout most of the winter, even in United States Department of Agricultural hardiness zone 5. Brussels sprouts is another great plant that survives throughout the winter outdoors without protection. If you wish to go an extra step and provide some type of frost protection, such as a row cover or cold frame, there are a number of plants that will survive the winter.
Grow a variety of salad mixes in a cold frame and eat fresh salads all winter long.
Lettuce is one of the easiest plants to keep alive throughout the winter – and the one I recommend beginners – or naysayers – try their hand at. Plant lettuce seeds in mid-August through mid-September. Cover the plants with a cold frame once the frost threatens. Most of the time it is not necessary to water or vent the cold frame during the winter months, however until winter sets in you may need to do this.
Tomatoes growing inside a cold frame in my Indiana garden on November 5, 2011.
A number of warm-weather crops, such as tomatoes can be kept alive for several more months by erecting a cold frame over the top of them before the temperature falls below 50 degrees Fahrenheit. Any stems, leaves or fruit that touch the plastic or row cover will sustain damage, so be aware of this. This is why tunnel houses often work best for taller crops.
Cabbage growing in a cold frame in my Indiana garden on November 5, 2011.
Cabbage – as well as most other cool-weather crops such as spinach, turnips, radish and carrots do fine under cover throughout the winter. The cabbage above was planted last spring. The area where it was grown received shade all summer long. Now that the leaves have fallen, it is in full sun. The plan is to leave it in the ground until I am ready to use it to make saukerkraut or coleslaw. In fact, I have an entire bed of cabbage planted in this particular cold frame.
Here are a few other plants that take a light frost and bounce back for more. Mix and match these – and just think how much longer they would last if given some frost protection.
Swiss chard still going strong after several frosts, including a killing frost.
Japanese red mustard doesn't mind snow, or frost - and grows all winter long in the open garden without protection.
Peas can handle some frost, but providing frost protection keeps them alive longer.
Snapdragons also tolerate frost, but growing them under cover results in taller plants that bloom much longer.
Extending the growing season is all about learning which plants tolerate frost and which ones need frost protection. Just like any aspect of gardening, it is trial and error. Keep notes. Learn what you did right and what you did wrong. In no time at all, you too can be gardening year-round, even if you live in a cold climate like I do!