by Connie Oswald Stofko
What is bolting versus flowering?
In both cases, the plant produces a flower.
Flowering occurs as a natural part of the plant’s life and generally doesn’t affect the taste of leaves.
Bolting occurs when a plant is stressed, often because the temperatures got too warm for that plant’s liking. The plant wants to reproduce before it dies, so it sends up a flower that will go to seed. Bolting diverts resources away from the leaves, which can affect the taste — and not in a good way. The leaves can be inedible.
Jen Weber, vice president and manager of Mike Weber Greenhouses at 42 French Rd., West Seneca, takes us through what you need to know about herbs that flower and herbs that bolt.
Herbs that bolt
Cilantro gets bitter when it bolts.
Plant cilantro in spring, between Memorial Day and Father’s Day, Weber said, and use it until the weather gets hot.
As soon as you see a flower bud start to form, cut it off. That will prolong the harvest of your leaves, she said.
Don’t just cut the bud off at the top; cut the stem all the way down to the leaves. If you’re doing it right, you’ll cut off a stem that is a quarter inch or half inch long.
Keep cutting the buds off. If you see a white flower, it’s too late. Your cilantro will be bitter.
If it gets away from you, you can buy a new cilantro plant at Mike Weber’s. They keep planting cilantro in batches, so they have new, fresh plants. You can also buy their Gardener’s Own brand plants at Wegmans.
Or you can skip the hottest part of the summer and buy a cilantro plant in mid- to late-August when the nights are cooling off, Weber said.
Unfortunately, cilantro seeds won’t overwinter outside in our area, so even if you let your plant go to seed outside, you won’t get a new crop in spring. You could save the seed and try to start a cilantro plant inside next spring.
Parsley bolts, but that doesn’t affect the flavor of the leaves, so you can let parsley go to seed. The seeds do overwinter, so you can have more parsley next year.
The parsley flower is ugly, but edible. The flower contains a lot of pollen, so if you’re allergic to pollen, don’t use the flower.
Weber added that you can get multiple harvests from one parsley plant. Parsley leaves grow back fast, so go ahead and cut them off and use them. Don’t be timid; more leaves will grow in their place.
Arugula, watercress and sorrel
You can think of arugula, watercress and sorrel as leafy vegetables, or you can think of them as herbs. They all bolt.
Bolting makes the leaves of these plants very bitter, and it’s especially true of arugula.
“Arugula is always bitter — and I like arugula — but one bite and you’ll spit it out,” Weber said. “You need to keep cutting the flowers off. When half the plant is flowers, toss it out.” And as it gets older, the leaves get tough, so you can tell just by looking at it that it’s past its prime.
Herbs that flower
Some chives flower once in spring while other varieties can flower off and on all season. The flowering doesn’t affect the taste of the leaves.
The flowers are pretty and edible.
When a basil plant flowers, it won’t affect the flavor of the leaves.
Clip off the flowers and the plant will get bigger.
Thyme, marjoram and oregano
Thyme, marjoram and oregano get small, pretty flowers. The flowers don’t affect the flavor of the leaves.
The flowers are edible, but they don’t taste like anything. You don’t really notice they’re there, Weber said.
Mint gets really big flowers, and the flowers don’t affect the taste of the leaves.
You can eat the flowers.
Because mint can spread easily in your garden, you may want to snip off the flowers before they go to seed.