By: Liz Froment

Head to your local grocery store, and you'll usually see a wall of produce filled with crisp, dark leafy greens. Kale, collard greens and swiss chard are ready to be quickly sauteed, stirred into your favorite winter stew or blended into a healthy breakfast smoothie.

You might wonder how these greens grow during the colder months. The answer? They're hardier and more resilient than you think.

Here's how it happens.

A Sweet Winter Surprise

If you're starting up a backyard garden, one of the common refrains is to set yourself up for success by focusing on hardy vegetables that can take a beating and still grow. Many leafy greens are in that group.

Kale is a popular option. There are a few varieties of kale and collard greens that tend to thrive in the colder weather. Kale will keep growing until the temperatures hit about 20 degrees.

Being able to thrive in cold weather is a bonus since kale tends to taste better when grown in colder weather as the leaves become sweeter. That's because some of the starch in the leaves starts transforming into sugar. Collard greens need temperatures just a bit warmer, managing to thrive until right around 32 degrees.

Over the last decade or so, kale and other leafy greens have gone through a resurgence in popularity and are now considered superfoods. That's because they are extremely nutrient-rich, chock full of vitamins A, C and K, as well as anti-oxidants—all of which are good for a healthy body.

How to Grow Kale and Other Hardy Leafy Greens

Farmers who want to get a leafy greens crop in the winter months need to make sure the plants are in the ground anywhere from three to six weeks before the first frost.

Some farmers will choose to start seeds in a greenhouse first and then transplant them to the soil before the winter growing season. They do this because the plants tend to become heartier as they mature — planting an already developing plant gives it a much better chance of survival compared to a seed. Transplants are about 6 to 9 inches high and need about four to six mature leaves before planting outside.

Once ready, the transplants get planted in rows, at least 6 inches deep and about 18 inches apart. Ideally, a sunny spot is best; it can help stimulate growth, which usually slows during the colder weather. Depending on the part of the country and how cold it gets, some farmers will put a light covering over the leafy greens—such as a layer of straw or burlap—that helps provide a little bit of protection against the elements.

Depending on the type of greens growing, harvesting can begin anywhere from 30 to 90 days. When it comes to harvesting, there are a couple of options. Plants are ready for harvest when the leaves are full-sized and mature. Farmworkers also pick off individual leaves, generally about a third of the plant at a time. Those leaves are sold as fresh leafy greens or mixes.

If the greens are harvested as a whole plant, they are stored right at about 32 degrees for upwards of two weeks. Farmworkers will harvest the plants, bundle them and put them into boxes. From there, the greens are stored until loaded onto trucks for delivery to the grocery store.

For plants that have individual leaves harvested off them, the process has to move much more quickly. The leaves are washed, packed and sold very fast; otherwise, they will go bad. These mixes are boxed, put on ice and shipped to their final destination.

From the Farm to Your Plate

Without farmers growing these hardy winter greens, our salads, soups, smoothies and side dishes would feel pretty bare. But now that you know these greens are grown fresh year-round and can taste better in the winter months, make sure you don't pass them over next time you're in the grocery store.

Liz Froment is a content marketing writer and strategist with a focus towards insurance, real estate and finance.