Basil produces purple or white flowers during Summer, if it has not been pruned. Once basil has flowered the leaves and flowers are still edible but the taste is often milder or even bitter. Prevent basil from flowering by pruning the top leaves of the basil every 2 or 3 weeks throughout the Summer.
Why Basil Displays Flowers
Basil is an annual edible herb that produces flowers, if it not regularly pruned.
If basil is left to grow then it will produce purple or white flowers (depending in the variety) which look beautiful and are a favourite for bees and pollinating insects as well as for ornamental purposes.
However once the basil is flowering, the leaves of the basil tend have less flavour and exude a weaker aroma, so if your growing basil for culinary purposes it is best to prune basil before it forms flowers which will stimulate more growth of the aromatic leaves for cooking.
Once basil flowers are spent the basil directs all its energy to producing seeds which you can collect to sow next year (although different basil varieties can cross pollinate so there is no guarantee the seeds will be the same variety of basil to the one you are growing).
Is Basil Safe to eat After Flowering?
Basil is an edible herb and the leaves are still safe to eat after flowering, although the taste of the leaves can be noticeable milder in taste or even bitter than the usual sweet aromatic taste of younger leaves.
The flowers and stems of basil are also safe to eat, however the stems often turn woody and the flavour is impaired, however the flowers have a mild and pleasant taste which are commonly eaten when scattered across salads as garnish or used in pesto.
If you are growing basil for culinary purposes it always best prune basil to prevent it flowering, or grow basil from seed in a timed succession (sow basil seeds once every two weeks in the Spring) so you have lots of plants with abundant leaves during the summer.
However a well pruned basil can produce tasty leaves all summer if it is watered properly and pruned diligently and remember the tender basil plants die off after the first frost so ensure you use all the leaves before it the plant dies in Winter.
How to Stop Basil from Flowering (for more edible leaves)
Pruning basil regularly, so that it does not exceed a height of around 8 inches is the best way to stimulate new growth of tasty basil leaves and to stop basil from flowering.
If basil is pruned regularly the plant is not at risk of becoming leggy and drooping and also pruning the top leaves allows light to the lower leaves which creates a more bushy plant with more abundant leaves.
Pruning basil is easy and it does not require any equipment as you can simply pinch and stems off ready for cooking so that they stay fresh.
I always pinch off the top two leaves of each stem for a good harvest of leaves and to ensure the light can reach the lower leaves to maximize the productivity of each plant.
(To learn how to prevent slugs eating basil, read my article for a method that actually works).
During the summer it is best practice to prune your basil once every two weeks to maintain a bushy plant with lots of leaves and to prevent it becoming leggy and displaying flowers.
The best time to prune basil is in the morning as this is when the essential oils are concentrated at their strongest.
If any flowers are developing simply cut them off with a pair of pruners which redirects the plants energy into producing leaves.
For a visual guide to pruning basil to stop it from flowering watch this helpful YouTube video for exactly what to do:
(Read my article, how to revive a dying basil plant).
- Basil produces flowers if they are not pruned regularly. The flowers and leaves are edible and safe to eat. The flowers heads produce seeds which can be collected and grown next years.
- Basil leaves often taste mild or bitter after flowering so pruning flower heads is important if you are growing basil leaves for culinary purposes.
- Prune basil when it is around 8 inches tall by pinching or pruning the top leaves off the basil. At the height of summer prune every 2-3 weeks to ensure the basil does not flower and to stimulate the growth of leaves.