The short answer
Basil flowers as it matures, often sooner in heat or stress. Pinch off flower buds if your goal is continued leafy growth; leave some flowers if you want pollinators or seeds.
Why this happens
Regular harvesting encourages branching and delays flowering. Once flowering is well established, leaves may become smaller or change flavor, though variety and growing conditions matter.
What to do
- Pinch growing tips above a pair of healthy leaves.
- Remove early flower spikes for leaf production.
- Provide ample light and consistent moisture.
- Start new plants periodically for a longer harvest season.
Keep in mind
Do not remove most of the foliage in one harvest. Use only treatments labeled for edible crops and follow harvest waiting periods.