Monday, November 4, 2013

Bolting in Vegetables

Bolting is the process of premature flower formation in response to high temperatures, as well as drought and starvation.  This unwelcome occurrence in leafy plants such as broccoli, cabbage, lettuce, and spinach,  takes the plant out of its leaf producing mode and switches over to flower and seed production.

Many vegetables are divided into two groups: cool season and warm season vegetables. Although in Hawaii seasons may vary little in temperature and many vegetables can be grown year around, some will do better when planted within the given time frame. 

Broccoli and lettuce are cool season vegetables. As long as the temperatures remain cool, the lettuce will continue to produce tender leaves, and the broccoli flower buds will remain closed. Generally lettuce and broccoli are planted from September through March/April.  During the hot summer months plants can bolt.  At higher elevations, cool season vegetables such as lettuce, beets, broccoli, cauliflower, chard, kale, peas, turnips and mustard, may be successful planted in late spring and summer.   

Warm season vegetables include tomatoes, cucumbers, melons, squash, peppers, corn and eggplant.