I started this blog with the intention of talking about the gardening challenges specific to the south coast–those of us straddling the shifting boundaries of Sunset zones 15 and 17. Gardening in a coastal climate has special challenges, and while we’re fortunate enough to have mild winters that allow us to grow food twelve months a year, trying to garden based on advice or plants imported from other areas can be very frustrating. Most of the country is concerned with frost dates, while we worry primarily about mildew and fungus. Most typical garden bloggers wring their hands over not having anything to do but seed shop during the winter months, while those of us along the coast are out turning over our winter salad beds, getting seeds in the ground, and worrying about weeds taking over everything.
Sunset magazine breaks the west coast up into bands or climactic “zones” that are way more useful for west coast gardeners than USDA hardiness zones or AHS heat tolerance zones. Any book that relies on USDA/AHS data with no reference to Sunset zones might be great eye candy, but it’s basically useless for plant selection in our area. Here are the critical books for plant selection in our area, including Golden Gate Gardening, the local bible if you’re gardening to eat.
“The coldest winter I ever spent was summer in San Francisco”
-(supposedly) Mark Twain
For readers who don’t live here, zone 17, where the fog drip and coastal breezes make it nearly impossible to grow heat-loving fruits and veggies, extends in a little squiggly, 2-5 mile wide ribbon from Bodega and Tomales Bay in the north, through Pt. Reyes, Bolinas, Stinson Bay and Sausalito, the entire city of San Francisco, down through Daly City, Half Moon Bay and San Gregorio. The winds from the bay also mean that a scant mile or two ribbon along the east side of the Peninsula from San Francisco down to San Jose, and about a five mile wide band along the east bay from Vallejo down through Oakland to Fremont, are also zone 17. In the summer, I keep a jacket in my car for the seven mile trip west to town. When the fog rolls in and sits right along Stage Rd, or on really hot inland days, a few miles further inland, it can be 70 degrees at my house and upper 50s with fog drip along the coast. This fog gets pulled up to the top of the Santa Cruz ridge most summer nights, blanketing all of our Zone 15 gardens with cool, moist air until mid-morning, when it’s drawn back out to the coastline. Why do I have smiling pictures of us cavorting on the beach near Pescadero? Because we go in April, when it’s sunny. With our coats on.
Most west coast states have a few zones, but California, and especially the bay area, looks like a kid’s fingerpainting, with crazy lines and splotches going every which way. There are 7 different zones just in this little area around the bay, and extending inward to Sacramento.
I thought you were going to talk about seeds?
Well, all this is really important for seed selection in your garden. Not only do you want to choose healthy seed from a reputable supplier, ideally you want to choose suppliers producing seed in similar conditions to yours. All those lavishly worded, effusive descriptions of the size and taste of such-and-so tomato are worth the paper they’re on if the supplier is basing that description on growing the tomato in a hot Missouri summer. If you have mild or cool summers, you need seed that is well adapted to quick production, and that develops good taste in a short window, even with cool nights.
I’m also a big believer in organic, non-GMO seed, since food crops raised conventionally to maturity for their seed have much more fertilizer and pesticide applied during their longer lifespan, and therefore a much higher carbon footprint. Not to mention the fact that since I don’t use any chemicals in my garden, I don’t want to spend time babying plants that have developed needing that crutch.
Where do I buy local California seed? And what should I grow?
As for what to grow, the UC Master Gardeners of San Mateo and San Francisco have a very helpful set of charts based on whether you are in a foggy, sunny, or hot area of the county. It is very important to be aware that local nurseries, based on customer demand, will stock vegetable starts even when it’s too early to plant them! Love Apple Farms will no doubt be selling tomato starts at the Flower and Garden Show in March, and the nurseries out here on the coast will have them available in April. The San Mateo Master Gardeners will be selling starts in late April. I know that in my little pocket of Sweet Hollow, which occasionally gets a light freeze even in May, I can’t put them out until June. I’ll still buy some at the show just for fun, because when will I have the chance to drive down to Love Apple? But I’ll keep them inside until late April, when I’ll gradually let them take more and more air on the sunny front deck during the day, until I’m finally ready to leave them out overnight when I plant them in June.
You can get local seed from the Petaluma Seed Bank (owned by Baker Creek Heirloom Seeds, so they carry seeds from elsewhere, but the staff is very knowledgeable about local growing conditions), or from mail-order California sources like Seeds of Change, Renee’s Garden, and Peaceful Valley Farm Supply. Just be prepared to spend some time if you go into Petaluma Seed Bank in person, if you are any kind of garden geek, it’s like a three-year-old walking into FAO Schwartz.