How to Grow Lettuce in Sonoma County
I was spoiled on growing lettuce in Santa Cruz, CA. Down there it’s lettuce country, people. The fog is no joke, and 80 degrees felt like a heat wave. We grew monstrous, succulent heads of Panisse – a buttery French variety as big as your head that could feed a family of four. We churned out Little Gems whose sweet hearts called for no more than a little salt and oil to make the perfect summer snack. And we sowed patchwork swaths of spicy mustard greens and savoys, painting the garden floor in a rich green ombre.
And then I moved up here. My first season growing lettuce in Petaluma came as a shock, and I had to rethink my methods. I clearly remember my first bed of lettuce heads growing on the southern edge of one of the Bounty’s main fields last season. We had about fifty feet of red heading lettuce, followed by fifty feet of a green salad leaf variety. Our heavy adobe clay soil takes a long time to dry out in the spring, so it wasn’t until mid May that we got these little transplants tucked into the ground. And then we waited. Rather, we ran around frantically for weeks, trying to get all of the longer season crops – the tomatoes, peppers and onions – into the ground and out of the crowded greenhouse.
And other than watering the lettuce, I essentially forgot about it, passing it by with a casual glance and expecting it to form beautiful, effortless heads in a matter of weeks. But the joke was on me. One day in the middle of one of those confusing June heat spells I did a double take when I saw what was to me a foreign site – a head of lettuce, BOLTING before it had even had a chance to head up! I ran up and down the bed tasting the leaves and discovered that they were all bitter. This is a family friendly blog so i will spare you the trail of obscenities that I’m sure escaped this farmer’s mouth. But Jimminy Cricket, that is not supposed to happen!
I’ve since changed my “rough and rowdy lettuce growing ways”, and am here to lay it all on the table for you in my own version of how to grow lettuce successfully here in Sonoma County.
It’s All About the Water
I know I’ve previously advised you all seriously consider your water use, but if you plan to grow lettuce, let ‘em have it! Lettuce is tricky in the heat, even more so in dry heat. Their shallow roots need frequent waterings – daily in most cases – but the leaves will also benefit from keeping fairly moist and cool. Your best bet, if faced with a particularly sunny and hot yard, is to employ some sort of overhead watering system. This could be a hose with a mist setting or, more practically, micro emitters that are set to go off once or twice in the heat of the day for just a minute or two. The amount of water used is actually quite minimal, and if set at a height just taller than your lettuce heads not much will be lost to the air. What the misting sprinklers are really doing is cooling the micro-climate around your sensitive lettuce leaves, keeping them happy and sweet (not bitter!). You can either run these for longer in the evening to give the roots the drink they need, or use them in combination with a drip system.
Choose Your Varieties Wisely
Here in Sonoma County, you can grow lettuce fairly easy from February or March through October. Make sure to choose heat-tolerant varieties for hot summer months! In order to have a continued harvest be sure to plant new successions (which can be just one head at a time if you want) every three weeks or so.
Jesse Pizzitola of First Light Farm in Petaluma, one of the best and certainly the funniest farmer around, is always kind enough to share his secrets with me. See, I get him laughing and then casually slip in a question about how to improve my irrigation or, in this case, what heat-tolerant varieties of lettuce have produced best for him. He may be on to me, but so far it’s worked like a charm. Jesse had great things to say about the Rhazes variety from Johnny’s if you are looking to try something new in your garden this season or next.
Do as I say, not as I did in 2013. If your lettuce seems stressed before it really sizes up, harvest it early. Eat ye of the leaves, make a big impromptu salad, feed your soil, and plant some more lettuce!
There are a few different ways to harvest lettuce. For the home gardener, your best bet is to pick or cut individual outer leaves when about 4″ long. You can also cut a whole plant or swath or plants down to about 4″, leaving the growth tip intact. You can come back and cut again another two or three times, once the new leaves are sized up.
Next time we’ll talk about how to get your garden ready for fall and how to ensure healthy crops that will last you til Thanksgiving and beyond. Hard to believe it’s nearly fall, but here we are! You still have time to plant many crops: lettuce, kales, broccoli, leeks, turnips, dill, beets, carrots, and radishes, to name a few. So savor your tomatoes and peppers, and start daydreaming about sweet fall kale and winter squash.