Green Up Your Vegetable Garden!
Fall is the time to “green up” your vegetable garden! From collards to turnip greens, swiss chard to arugula, there are countless varieties of greens that are easy to grow, and do particularly well in autumn. Many popular greens are cool season plants, and the harvest tends to be longer and sweeter in the fall. Temperatures are cooling rather than warming, and the days are getting shorter, which makes plants less likely to bolt or form a flower. The greens are sweeter with cooler nights, and many pests become less active. Select cold-hardy varieties to harvest beyond frosts and freeze. The hardiest varieties will yield an early spring harvest as well.
Most of the winter greens can be grown for either for smaller-leaved salad mix using the “cut-and-come-again” technique, or for larger leaves suited for cooking. ‘Siberian’ and ‘Winterbor’ are hardy winter kales, and ‘Vates’ and ‘Champion’ are recommended winter collards. Mustard greens come in a variety of colors spice levels. Mild mustards such as ‘Fun Jen’, ‘Tendergreen’, and ‘Mizuna’ can be enjoyed as a lettuce substitute. Milder purple mustards such as ‘Ruby Streaks’ add color to fall salads. A great overwintering mustard is ‘Chinese Thick Stem’, available through a few regional seed companies. Chinese cabbage varieties are also excellent in fall. Choose a leafy ‘Pac Choi’ for continuous harvest or Bok Choy if you want to harvest the whole head.
Spinach and arugula are some of the hardiest and most versatile cool-season greens. ‘Bloomsdale’ is a popular winter spinach variety. Arugula has two general types- rocket or roquette, and sylvetta. Sylvetta has a stronger, smokier flavor. A very flavorful cold-hardy variety is ‘Ice-Bred’, available from a few regional seed companies.
Lettuces can also be grown as “cut-and-come-again” greens or head lettuce. ‘Deer Tongue’ ‘Buttercrunch’, ‘Salad Bowl’, and ‘Rouge d’Hiver’ are excellent varieties for continuous harvest. Lettuces can be sown directly but they do not germinate when soil temperatures are consistently above 70 degrees. For an early start, sow them inside and transplant them outside after 4-6 weeks. Or, cover the seedbed with a shade cloth during germination.
Turnips, radishes, and beets are popular fall root crops whose tops are also edible. Daikon radishes are versatile in the kitchen, and produce a large, white taproot that can alleviate soil compaction. ‘Misato rose’ and ‘Watermelon’ radishes are popular because of their beautiful pink flesh and large size. ‘Purple top’ and ‘White egg’ are sweet, hardy turnip varieties. For something different, consider growing rutabagas, which are a nuttier and slower-growing relative of the turnip. Harvest radishes and turnips before hard frosts. If you can’t eat them, leave them behind to cover the soil and recycle nutrients in the field.
Plant your fall greens in a well-drained site with good sun exposure and away from plants grown in the same season from the same plant family. Take soil test and amend your soil as recommended. Test kits are available at the NC Cooperative Extension Center (120 Hospital Ave NE, Lenoir), and are performed free of charge until Thanksgiving through the NC Department of Agriculture. If no soil test is done, incorporate 3 lb 10-10-10 or equivalent fertilizer per 100 square feet before planting. If you want to keep harvesting and temperatures are favorable for plant growth, sidedress with bloodmeal or a nitrogen fertilizer 2-5 times throughout the season.
Sow beets, kale and collards by mid- or late-August. Other greens, turnips, and radishes can be sown into early September.
After incorporating lime and/or fertilizer, you can either transplant started seedlings or sow seeds directly. One way is to sow is to dig a shallow trench and “dribble” seed in parallel lines 4” apart for salad greens or 12” apart for cooking greens. Cover the seeds with soil, and provide ample water for germination. Plant slightly deeper than in the spring as soil temperatures are still very warm.
The first harvest you make if you direct seed will be to thin out the rows to your target spacing. Pull up plants between those with the desired spacing, snip edible leaves into a bowl, and compost the crown. Thin to 4” for mixed salad greens, or 6-12” for head lettuce or cooking greens. From then on, cut all the leaves off of one-third of the greens, 2-3” above the soil. Wait 2-4 weeks between each harvest, and harvest the other sections of plants in the meantime. For cooking greens, harvest the outermost and largest leaves each time, leaving at least 4-5 leaves or 40% of leaves on the plant each time.
For frost protection and to extend your greens harvest, place row cover over your crops. Support the row cover with stakes or hoops, and secure from wind. Placing row cover over rows during germination can also help germination by keeping in moisture, and keep out pests such as the cabbage webworm and imported cabbageworm. For more information on fall greens and gardening, see: https://content.ces.ncsu.edu/growing-a-fall-vegetable-garden. Contact the Caldwell Extension Center at 828-757-1290 with any other gardening questions.