By Trish Grenfell, UC Master Gardener of Placer County
Q: I planted basil this spring and am unsure how many leaves I can remove without killing the plant. Will it regrow after I scalp it?
A: Basil is wonderful, not only as a culinary experience, but if you place leafy bouquets in water, the spicy fragrance will delightfully summerize your kitchen. Here are some quick tips to maximize your harvest.
Don’t cut the plant until it is 6-10 inches high (exception: dwarf varieties). For the first harvest, clip stems just above the second set of leaves (counting from the bottom). New stems will form at this juncture, giving you a bushier plant. Basil will benefit from regular clipping about twice/month. New leaves have the best flavor.
Don’t wait for one big harvest at the end of the season. By then most of the leaves will be past their prime and bitter tasting. During the growing season, water often and consistently, as you would a tomato plant. Basil is a tropical annual that needs lots of water to produce those succulent leaves.
When daytime temperatures rise above 80 degrees, basil begins to flower. Resist the impulse to just pinch off the tip. Pinching off the flower spike (it’s edible too) doesn’t halt the flowering—it simply makes way for the next flower stalk. Instead, cut the budding stalks at least four leaf nodes down the stem. This will shock your basil out of flower production and back into leaf production, which is exactly what you want. Once a basil plant goes to seed, the existing leaves lessen in flavor.
If you don’t pinch or harvest, the plants will grow tall and gangly, with few leaves and will bolt to seed. You can continue harvesting as long as there are leaves left on the plant to keep it going. Basil is very sensitive to frost and will be one of the first plants to go in the fall.