What should I do if my lettuce starts flowering?
Written by
Benjamin Miller
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Lettuce bolting occurs when leaves develop into flower stalks and produce seeds. This indicates that the salad plant is stressed, and flowers have formed, meaning the edible stage is coming to an end. If plants start flowering, pick them instantly as the flowers bolt to seed overnight, and the leaves will be unpleasantly bitter. Factors that contribute to lettuce bolting include the flowering season (heat), long daylight hours, and other environmental factors.
Immediate Response
- Harvest Promptly: Pick entire plant within 24 hours
- Bitterness Test: Taste outer leaves before full harvest
- Seed Saving: Allow some flowers to mature for future planting
Prevention Techniques
- Shade Provision: Use 30% shade cloth above 24°C (75°F)
- Moisture Control: Maintain consistent soil dampness
- Variety Selection: Choose slow-bolt types like 'Winter Density'
Stop it from going to seed before it has the chance. Grow slow-bolt varieties suited to your climate. Provide afternoon shade when the heat reaches its peak, and supply the soil below with plenty of moisture by allowing drip irrigation to do its work. Place 5 cm (2 in) of straw mulch over the soil, which helps cool the roots. All of these things act to postpone the flowering process for weeks.
If it bolts, then you may pull up the whole plant. BITTER LEAVES will be much prized in your cooked dishes: a good thing for soups, where the bitterness will evaporate. Save seeds from the mature flowers for colour, and also for the following season. I save seeds from my earliest bolters, selecting for a hot variety.
Set out or plant crops to avert the extremes of summer evenings. In warm climates, sow early spring or fall crops so that they can be harvested before the heat arrives. Succeed plantings every two weeks. Watch for the length of the days, for if more than 14 hours of daylight are given, bolting occurs at any temperature.
After harvesting bolted plants, apply compost as a fertilizer. Annually rotate your planting locations. Plants that experience bolting are usually under some form of stress that will likely continue if we don't improve the soil. To replenish my soil after harvesting bolted lettuce, I will put a nitrogen-fixing bean crop in its place.
Read the full article: When to Harvest Lettuce for Best Results
