
Cool Season Vegetable Gardening
Cool Season Vegetables in Sonoma
By Janet Barocco, Sonoma County Master Gardener

Cool-Season Gardening is Cool
What’s not to like about cultivating a cool weather garden? Personally, it’s my favorite time to garden, and I’ll give you two reasons why: I get a fresh, robust harvest in autumn, winter and early spring (depending on type of plant and variety), and with no, or low-stress, watering!
Robust harvest
Keep your rain gear handy at the back door; if you get your plants and seeds in on time, you’ll be making frequent trips to the garden for greens, crisp peas, tender roots, cabbage and herbs, in autumn, winter and early spring. It’s interesting that many cool weather crops will sweeten and deepen in flavor with colder weather.
Low-stress watering
You’ll need to monitor watering of your seedlings and transplants during the drier months of August and September. But, as the days shorten and autumn rains commence, Mother Nature will take over the irrigation.
Now that we’ve sung the praises of planting a cool season garden, let’s get started.
Timing is Everything
After the summer solstice here in the northern hemisphere, in late June, the days grow progressively shorter, leaving less sunlight for plant growth. If you want an autumn/winter harvest, you must sow and transplant in August and September, or there will not be the sufficient amount of light to sustain the growth of the young plants. We can’t reiterate enough how important it is to get cracking on your cool weather garden in late summer, as odd as it feels to be planting winter crops when it still feels like high summer!
If sowing seeds, check the seed packet to determine the number of days to germination and to maturity. With regard to the latter, remember that many greens, roots and herbs are delicious when harvested young and tender, and don’t require your waiting the entire time to maturity to pluck and eat.
I like to mark the number of days on a calendar, which gives me an instant visual timeline (and record) of what I plan to plant.
What’s for Dinner?
Let your appetite guide you in what to plant. Sit down with the family and make a list of favorites. Check with local nurseries to see what starts are in. This is a great way to learn what’s in season and when it’s time to get planting. And, check the list at the end of this article for ideas.
Be realistic about the time you have to garden, and to handle the eventual harvest and its preparation. Try to keep it simple.
Make space
Planting at summer’s end can be challenging given that most of us have limited kitchen garden space. Chances are you’ll need to sow or plant in and around existing summer vegetables that are at peak production. It’s a bit of a puzzle, but don’t despair – it is possible to do both. Here are a few ideas to help fit the pieces together:
1. Tuck seedlings or carefully sow seed around existing plants. For example, scatter lettuce seeds around tomatoes and peppers.
2. Dig a brand new area and design your planting scheme from the start.
3. Plant and sow in large containers such as half wine barrels. I have two half wine barrels at the entrance to my kitchen garden. They each have a welded wire column in them, with a tomato plant at the center. I’ve also placed a wire arch spanning the two barrels, with scarlet runner bean vines growing up from both sides, meeting in the center of the arch. Parsley and nasturtiums rim the barrel perimeters. Marigolds and lettuce would also do well there.
Prepare the soil
Keep your soil healthy by working in good organic compost beforehand, or side dress existing plants. Dig and water into the top few inches. Or use a foliar-type spray fertilizer such as fish emulsion on your young plants.
Cool-weather Kitchen Garden Crops
The following are easy to start from seed, but of course you can also purchase starts at your local nurseries, starting in late July and early August.
Beets, bunch onions, calendula, carrot, chives, dill, greens (bok choy, Swiss chard, kale, mustard, radicchio), leeks, nasturtium, parsley, parsnip, peas.
Usually purchased as starts, these can also be sown indoors mid-summer, to be transplanted to the garden in August and September:
Artichoke, broccoli, cabbage, cauliflower, fennel bulb.
Others:
Fava Beans: sow from August – December
Asparagus: plant bare root in January-February
Garlic, onions, shallots: check local nurseries or mail order in early autumn for bulbs.
Suggested Reading for Sonoma County food gardening:
Sunset Western Garden Book
The Kitchen Garden Grower’s Guide
Goodlife Garden