Plant guide:ðŸĨĶ Broccoli
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Growth

Broccoli Bolting and Flowering Prematurely

Commonly affects: Brassica oleracea var. italica (Broccoli)

The plant sends up a tall flower stalk with small yellow flowers before forming a proper harvestable head, or an already-forming head opens into loose yellow flowers.

Potential Causes

  1. 1Heat stress or a sudden warm spell triggering the plant's flowering response
  2. 2Extended cold exposure early in the plant's life (vernalisation) followed by warming, especially in overwintered plants
  3. 3Stress from drought or nutrient deficiency accelerating the shift to flowering
  4. 4Planting too late in spring, letting the plant mature into hot weather

Solution Steps

  1. 1Harvest immediately once bolting begins, since the head is still edible if caught early
  2. 2Plant broccoli early enough to mature before hot weather arrives, or in autumn for cool-season maturity
  3. 3Keep plants consistently watered and fed to reduce stress-triggered bolting
  4. 4Choose bolt-resistant varieties for regions with unpredictable spring heat

Prevention Tip

Timing broccoli to mature in cool weather — either an early spring or autumn crop — is the most effective way to prevent bolting.

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