You grow lettuce in the summer!
It seems unfair -- just when we really need lettuce as the foundation of a summer salad, the lettuce wants to pack up and spend its summer at Lake Tahoe (or some other cool spot). Here's how you can have your lettuce and heat it too. 
Horses bolt and so does lettuce
Lettuce prefers the cool days of spring and fall with air temperatures in the 60s. When the weather warms up lettuce will often bolt right out of your garden bed. In the world of lettuce, bolting means that the plant sets a flower and grows a seed stalk -- which makes the lettuce leaves bitter. What causes bolting? A combination of more sunlight in the longer days, and the hot summer weather.
How to grow lettuce in the heat
What's a summer gardener to do? First, alter your lettuce growing climate to make it cooler and shadier. Second, grow heat tolerant lettuces.
Cool down the summer weather for your lettuce
As gardeners, we adjust to the seasons. If your spring vegetable patch is in full sun then don't plant summer lettuce there -- instead, plant summer lettuce where it will get morning sun and afternoon shade (morning shade and afternoon sun will give too much heat). This might be the time to plant lettuces in amongst your part-shade ornamentals. Want variegated foliage? We've got some stunners, like 'Freckles', shown above. Can't move your vegetable patch? Then adjust the sun's rays by providing a shade cloth covering for the lettuce part of the bed. Need support for your shade cloth? We explain how to build low tunnels over your raised beds.
The ABCs of growing lettuce
Tricia plants, grows, and harvests lettuce in our latest video. There are four basic groups of lettuces: Bibb, Crisphead, Leaf, and Romaine. We make it easy for you to find the lettuce you want by going to our Lettuce Seeds page and from there click Features and then Heat Tolerant to see varieties that grow best in summer. You'll see all the lettuce varieties we carry, in seed packs on up to bulk sizes.
Heat Tolerant Lettuces
There are Heat Tolerant varieties in all four lettuce groups:
Bibb/Butterhead Buttercrunch, Pirat, Divina
Leaf Black Seeded Simpson, Green Salad Bowl, New Red Fire
Romaine Little Gem, Parris Island Cos
Container gardening -- an easy way to modify climate for lettuce
One of the joys of container gardening is that you get to play Mother Nature. Is the sun too strong for your lettuces? Pick up the container and move it to a part-shade location. Our vegetable gardens are rarely right outside the kitchen door, but you can grow containers of Leaf lettuces just steps away from your kitchen sink -- cut some leaves, rinse, spin, toss, and eat. Head lettuces like Romaine, Bibb and Crisphead need to grow about 50 days to harvest, so let them get on with it out in your vegetable bed. But the Leaf lettuces are ideal for containers -- pick the outer leaves and let the center continue to grow. This is called a "cut and come again" method of harvesting. Whether you grow in containers, mixed in with your ornamental plants, or in a vegetable garden -- plant some lettuce this summer.
For more information on keeping plants perky during the summer, see our Resource Center.
4 comments
Robb, if you are referring to Agribon, it will not help to cool your plants, you are correct it will hold in heat. You would be better off with shade cloth.
Can white cloth be used for shading lettuce or does it hold in to much heat?
Hi,
Are there varieties of iceberg lettuce and cabbages that can grow on low altitudes of less than 1000 feet and temperatures ranging 28 to 33 degrees Celsius along the equator (tropical climate)
Ali, no not really. One thing you could do to help cool them down a bit is to put up some shade cloth. But for lettuce, I would stick to the romaine varieties; they are the most heat tolerant.