My summer lunch staple is often a meal of heirloom tomatoes, mozzarella cheese, and basil vinaigrette. Recognizing that the lone basil plant on my window ledge wouldn’t provide enough leaves, I recently added a lush pot filled with three more basil plants. Two weeks ago and well into summer, the plants seemed to pull water the instant they were watered. All of sudden, I noticed tall green flower stalks appear where there should have been new leaves. I remembered the gardening adage, and pinched out the flowers to encourage leaf growth. It was too late as the plant bloomed with white flowers; my basil plant had “bolted” or gone to seed.
A plant bolts when the weather becomes too hot – a survival mechanism for the species. The stalk rapidly produces flowers, which then go to seed. Bolting is a common gardening term, but it represented nothing that I had encountered in all the years that I had grown basil. I would have not even realized the connection, if not for a Skype chat with my uncle who asked me to look out for bolt-free cultivars of spinach. (Spinach, lettuce, broccoli, cabbage, and cilantro are some of the plants that bolt.) Plants that have bolted become inedible, and their stems become woody and tasteless and the leaves turn bitter. The leaves on my basil plant had just started turning bitter, and I immediately stripped them off the plant. I used the basil leaves to make pesto and basil butter in order to preserve what was left of their aromatic sweetness.
Some Common Sense Tips To Prevent Bolting:
- Move the plants to a shady location once the weather becomes hot.
- Cover the topsoil with mulch to keep the roots cool.
- Cut back the existing leaves further down the stem, forcing the plant direct its energy towards producing more leaves.
- Deadhead or promptly remove the buds as soon as they start to appear.
- If starting from seeds, stagger when the plants mature (early spring to fall) so as to have a continuous supply of new plants.