As the end of August approaches, we gardeners are savoring our harvest of tomatoes, peppers, zucchini and other summer bounty. Days are getting shorter and the light is starting to change, signals of a shift in the seasons. Cool-season vegetables are just on the horizon.
With autumn approaching, we need to be thinking about amending our gardens and getting them ready for planting the kinds of vegetables that thrive in cool weather.
Many Napa Valley microclimates are conducive to these cool-loving edibles. Depending on the crop, the best planting time for seeds and nursery seedlings ranges from late August to early September.
Vegetables that do well in fall and winter include cole crops (brassicas), root vegetables and leafy greens. Among the brassicas, consider growing cabbage, Brussels sprouts, cauliflower and broccoli. Root vegetables to plant now include turnips, carrots, radishes, parsnips and beets. As for leafy vegetables, late summer is the ideal time to start lettuces, chard, kale and bokchoy. Asparagus and potatoes can also be planted now.
Some of these cool-season vegetables are “two-for-ones,” like beets and turnips. We can (and should) eat both the roots and the nutritious greens. Most of these fall and winter edibles are rich in vitamins and antioxidants.
If you are planting from seed, don't delay. Seeds will sprout quickly in late summer's warm soil, and your seedlings will get off to a good start before the weather cools. You can plant nursery seedlings now and into September; local nurseries have a good selection now.
Napa County Master Gardeners have a useful planting calendar, which you can find at http://ucanr.edu/sites/ucmgnapa/Gardening_Books/.
I grew broccoli, spinach, chard and leeks successfully when I lived in Grass Valley, with its cool nights and warm days. These crops also do well when grown in autumn in Napa Valley.
Companion planting is a great way to use space wisely if you have only a small garden bed or are using containers. I personally have a small space and use containers. Broccoli and baby bokchoy or spinach work well together. You can plant herbs and scallions or leeks together, or beets and radishes with lettuce.
Be sure to amend your soil with compost before planting cool-season vegetables to ensure a bountiful future harvest.
Free workshop: Napa County Master Gardeners will conduct a workshop on “Home Composting” on Saturday, September 6, from 9:00 a.m. to 10:00 a.m. at the Yountville Community Center. Learn how to turn yardwaste and kitchen scraps into rich compost to use as a soil amendment or mulch in your garden. The workshop is free but Pre-registration is required. No phone registrations are accepted. You will receive a confirmation and directions after registering. Questions? Call (707) 257-9200.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. Napa County Master Gardeners ( http://ucanr.org/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.