You likely know how frustrating it can be to have lettuce bolting if you’ve ever gone out to your garden to harvest a nice bunch of lettuce only to find it growing straight up with bitter-tasting leaves.
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Or if you haven’t experienced your plants bolting before, maybe you’re wondering what that even means.
Bolting is when a plant flowers out. The plant will usually grow a large flower stalk that gets tall and then goes to seed.
And at the end of the season, this is usually no problem, but when you’re wanting to harvest your lettuce plants it can be pretty frustrating because once the plant has bolted the lettuce leaves are tougher and they turn bitter.
Unfortunately, there isn’t much you can do once it has happened but there are a few things you can do to help prevent it.
So first let’s cover what causes it.
What Causes Lettuce Bolting
The biggest factor is day length.
Some crops are triggered to bolt as day length increases, while others are triggered to bolt as day length decreases.
Growing lettuce is best to do during short days, in moist soil, and when the weather is cooler.
Once a certain number of daylight hours has been met the plant will switch from leaf production to flowering.
Another factor that may cause lettuce to prematurely bolt is heat and water stress.
But after many studies that have been done, it has been concluded that the increase in daylight is the biggest factor that contributes to lettuce bolting.
Lettuce and spinach are alike in the sense that they are both sensitive to the longer days, so to have the most success when growing either, it’s best to plant them early in the season, keep them shaded well. Or plant them later on in your fall garden as the days begin to shorten.
How to Prevent Your Lettuce From Bolting
If you’ve experienced this before, the best thing you can do for future plantings is to prevent it from the start.
So here are a few great tips!
1.) Plant bolt resistant and heat tolerant varieties
A few heat tolerant and slow to bolt lettuce varieties include:
2.) Plant during the optimal time of year
Lettuce is a cool-season crop so as soon as the weather allows, you should get your plants started.
This could be planting straight in the ground if the weather permits or by starting your seeds early in a greenhouse so that your transplants are ready as soon as you can plant outdoors.
You should also use succession planting and plant often so you can get as many harvests as possible while the right weather conditions are present.
But no matter what lettuce variety you plant, it’s very unlikely that you’ll be able to grow it all summer long during the heat of summer while days are long.
So if you can’t get your lettuce going early on in spring, you can plant it again in fall.
3.) Provide shade for your lettuce
It’s always best to plant cool-season crops such as lettuce, broccoli, spinach, and kale when the weather is cooler.
But you can also help them out by planting them in the shade so if high temperatures arrive sooner than expected your plants can still have cooler growing conditions.
A few ways that you can shade your plants is by:
- Putting up a shade cloth.
- Planting in an area that already receives morning sun and afternoon shade.
- Or by using companion planting methods. You can plant vegetables such as spinach, lettuce and arugula in the shade of larger plants like tomatoes.
Frequently Asked Questions
Below are some of the frequently asked questions by other vegetable gardeners.
How to Trim Bolted Lettuce?
You can easily trim bolted lettuce with gardening shears or with a sharp knife, but since the lettuce will be bitter to eat, it’s best to just pull the plants out.
You can then replant if it’s early enough in the season.
Can You Eat Bolted Lettuce?
Yes, you can eat bolted lettuce but you probably won’t want to.
Once lettuce begins to bolt it starts producing compounds called sesquiterpene lactones.
They are the plant’s natural defense mechanism to ward off pests so that it can successfully produce seeds.
Kind of amazing huh!
But unfortunately, the compounds make the lettuce taste really bitter.
What Can You Do With Bolted Lettuce?
You can feed it to your animals such as chickens or goats.
Cut it back and let it resprout. Not all lettuce varieties will grow back though. For example, most head lettuces will die but most leaf lettuces will grow back.
So you can cut it back and hope for another crop. Although most lettuce is so quick to sprout and grow, I usually prefer to just replant once it’s flowered out.
You can also let the bolted lettuce flower out and then keep it in your garden to attract beneficial insects and pollinators.
Or, once the lettuce goes to seed you could collect the seeds to plant for next year.