Make Sure To Harvest Your Lettuce Before Your Plant Bolts And Turns Bitter And Inedible
Reviewed By COLIN SKELLY
Colin is a Horticulturist and Horticultural Consultant with experience in a range of practical and managerial roles across heritage, commercial and public horticulture. He holds the Royal Horticultural Society’s Master of Horticulture award and has a particular interest in horticultural ecology and naturalistic planting for habitat and climate resilience.
Contributions From EMILY CUPIT
Emily is a Gardening Writer, Photographer and Videographer from Derbyshire, UK. She is the Founder of Emily's Green Diary - a community of more than 75,000 people who share in her gardening journey.
If you harvest lettuce from your own garden to take with you to your kitchen table, it will be packed full of flavour that store-bought lettuce just won’t have.
You can enjoy this tasty veggie right from June clear through to November.
But when exactly do you harvest lettuce?
This depends – of course – on when you sowed the seeds.
However, two additional factors come into play. First, the time to maturity of the given variety, and, second, your personal likes and needs.
All types of lettuce can be harvested young or when fully mature.
Most varieties will be ready for harvest from 8-12 weeks after germination though a few varieties take longer.
| Difficulty | Easy |
| Equipment Required | Gardening gloves, sharp knife or secateurs/scissors or mini-secateurs (optional) |
| When To Harvest | Head lettuce from 8 to 12 weeks after planting |
Harvesting Loose-Leaf Lettuce
Loose-Leaf lettuce can be harvested on an ongoing basis similar to how you harvest chard.
Leaves can be picked from about 6 weeks after sowing or when the outside leaves have grown to about 15cm.
The idea is to take what you need from each plant while allowing it to keep growing and producing fresh leaves until the end of autumn.
Pick three or four leaves from each lettuce, going only for the outside leaves.
Gently pull away a leaf and snip it at the stem a few centimetres off the ground.
If you use mini-secateurs or scissors you run less risk of inadvertently slicing through other leaves.
Also, instead of bringing the scissors or mini-secateurs into the plant, run them at a tangent to the plant so that you are sure to isolate the leaf you want to cut.
You can – of course – harvest the entire Loose-Leaf lettuce in one go.
When To Harvest Head Lettuce
As stated above, most lettuce varieties will be ready for harvest in from 8 to 12 weeks, though a few varieties take longer.
You may harvest lettuce young to suit your needs, but you must harvest it by its ‘Expiry Date’.
If you don’t and the plant bolts, the lettuce will become bitter and inedible.
“Start harvesting early and often, as if you wait too long your lettuce will start to bolt and you’ll have a lettuce glut on your hands,” shares Horticultural Consultant Colin Skelly.
“Little and often is my tactic when it comes to harvesting lettuce.”
Fortunately, lettuce throws up a tell-tale signal that you may soon lose it!
For all types of head lettuce that have a round shape, if the round head shows the least sign of elongating, that lettuce should immediately be harvested as it will otherwise bolt.
You can pre-empt this signal and still harvest lettuce at its peak of maturity.
For all hearting lettuce, including romaine or cos, simply peer into the lettuce, parting a few leaves as necessary.
If it has formed a heart, it is fully mature and is ready to harvest.
Harvesting Technique
Lettuce is best harvested in the early morning, especially in summer or hot weather, otherwise you may well be picking limp, tired heads.
To harvest, firmly grasp the lettuce head with one hand, gently pull up and over to one side, and on the other side with the other hand, using a pair of secateurs or a sharp knife, cut the stem cleanly close to the soil.
You may struggle the first time or two that you harvest lettuce but you’ll soon get the hang of it.
If you plan to harvest some of your lettuce crop early, then, instead of harvesting several heads growing adjacent to one another, you could pick every other lettuce (assuming you don’t need to clear a patch of ground for some other crop).
Taking alternating heads will allow the plants left behind room to develop even more fully.
Storage
After bringing in your lettuce, pull out leaves in twos and threes, then put in a shallow bowl and wash in cold running water.
The best place to ‘store’ your freshly-harvested lettuce is on the kitchen table!
The delicious taste will diminish the longer lettuce is stored.
If you must store your harvested lettuce for a longer period of time, wrap it tightly in a polythene bag or cling film that has a few tiny holes, and store in the fridge’s crisper.
The longer you keep it in the fridge, the less flavourful and succulent it will get.
We suggest you keep it in the fridge for a maximum of four days.
