Provide moist soil
Try growing lettuce in a moisture-retentive soil to prevent the plants from bolting. To increase its water-holding capacity, add compost or manure annually.
Use available space
If you’re short of space, try planting lettuces as a catch crop between sowings of cabbages. The lettuces will be ready to harvest before the cabbages take up all the space.
Try watering lettuces at the base and not in the heart of the plant. If the heart is soaked, it may eventually rot.
Get rid of weeds
Make sure to use a hoe to keep rows weed-free. There’s an old saying, “Hoeing once is the equivalent of watering twice.” This is because hoeing loosens the soil and eventually lowers the rate of evaporation of moisture and, as weeds are competitors for water, getting rid of them gives the lettuce a better chance.
Pick at the right time
To test whether a hearting lettuce is ready to pick, feel the heart–it should be both nice and firm. If it is not, leave the plant in the ground for a few days more and try again.