Bolting in iceberg Lettuce. What causes it? How to prevent it? What to do if your lettuce plant has bolted?

Harvesting home grown vegetables after months of effort feels rewarding. Doesn’t it? Taking care of them makes a good part of our daily schedule. We observe for their health and do all we can to keep them healthy.

Farming or for that matter home gardening, brings with itself a lot of problems. One of them is premature bolting. Though bolting is same as flowering, it may not be desired in leafy vegetables like spinach, lettuce or celery. In this article, we will look specifically at bolting in iceberg lettuce.

What does bolted iceberg lettuce look like?

You know lettuce has bolted, when its main stem elongates. It has leaves arranged in spirals on the main stem. This stem produces flowers and eventually seeds.  Bolting is a survival mechanism as we will come to know soon.


 Why does Lettuce bolt?

Bolting is a survival mechanism through which plants try to generate offsprings. When a plant faces environmental conditions that are not conducive to its growth, it tries to create seeds so that next generation can kick in. It is nature’s own way of continuing life cycle of a plant.

Iceberg lettuce thrive best in cold climate and need low exposure to sunlight. Thus, increase in temperature or long exposure to daylight may cause iceberg lettuce to bolt. Another factor that can cause iceberg lettuce to bolt is using wrong kind of manure or nutrition for the plant. Bolting is equivalent to fruiting. If one ends up giving a fruiting nutrient/manure to lettuce, it can also lead to bolting. Lettuce also bolts under drought-like conditions. Water stress accounts for unfavorable surviving conditions leading the flower to reproduce.

Now, we do have a little understanding of what caused lettuce in our garden to bolt. Question that arises next in our minds is- What happens when lettuce bolts? Is it still consumable? Is it marketable?

Here is a list of chemical and physical changes accompanied with lettuce bolt.

  • It tastes bitter
  • Poor or under- developed Head
  • Greater white sap like content found in stems and leaves (mainly stems)

Poor head development and bitter taste makes lettuce unfit to market. So for anyone growing lettuce for consumption, bolting is a big problem.

How to prevent bolting?

Bolting as a problem is well understood. So our natural response is to prevent it.

  • Since genetics play a role in premature bolting, growing slow bolting varieties will be a natural help.
  • Soak the grow medium for 1-2 days before sowing seeds
  • Grow lettuce under shaded conditions like under taller plants
  • Water lettuce regularly to avoid water stress and keep grow medium cool. This also helps keep the leaves succulent.
  • Easiest of all. You can always pick them when they are young enough. Lettuce also flowers when it reaches its maturity.

What can be done with bolted lettuce?

 If your lettuce has already bolted, there are a few ways to make it useful.

  • Make soup
  • Let it seed
  • Animals like rabbits and chicken would feed on them so give it to some animal shelter.
  • Use it as compost
  • Use it as insect resistance for other plants. The bitter compound that makes lettuce taste bitter also repels burrowing insects.

The best you can do is to use some of its leaves for soup and allow it to seed. Use these seeds for further propagation.

Happy Farming!

















Gaurav is an entrepreneur whose first Start-up was focused on providing services to patients suffering from Chronic Diseases. While researching about the causes of lifestyle diseases and the ways to reduce their incidence, he chanced upon the idea of growing healthy and nutritious food using advanced farming techniques.

He founded CityGreens with a mission to enable City Dwellers to access Safe, Healthy and Fresh food.

Got a Query? or Have something interesting to share that can help other urban farmers? Leave a comment

Your email address will not be published.