Broccoli Plant Blooming Yellow Flowers
broccoli flowers1
(Image credit: enrouteksm)

Broccoli is a cold weather crop, meaning that it grows best in soil with temperatures between 65 and 75 degrees F. (18-24 C.). Warmer than that, and the broccoli will bolt, or go to flower. Many gardeners only have a short window available to them where the temperatures are within that range. An average gardener must contend with temperatures that rise quickly and stay well above the ideal 65 to 75 degrees F. (18-24 C.) range, but there are things you can do to prevent bolting broccoli. Let's take a look at the best way to grow broccoli in hot weather.

Hot Weather Effect on Broccoli

When broccoli gets too hot, it will bolt or start to flower. Contrary to popular belief, hot weather will not cause bolting broccoli. What actually causes bolting broccoli is hot soil.

Tips for Growing Broccoli in Hot Weather

The best way to prevent broccoli flowers from appearing too early is to keep the soil the broccoli is planted in cool.


The best way to grow broccoli if you expect hot weather is to make sure that the broccoli plant is well mulched. The hot weather effect on broccoli will only happen if the heat gets to the roots. A thick layer of mulch will help keep the roots cool and prevent the broccoli from bolting.


Another tip for growing broccoli in hot weather is to water frequently. The cool water will help keep the soil cool as well and will stop bolting broccoli.

Row covers

Keeping the direct sun from the plants and soil is another way to prevent broccoli flowers and keep the ground cool. Row covers are frequently used to keep cold weather crops producing longer.


An excellent way on how to prevent broccoli flowers is to harvest early and frequently. Broccoli is a cut and come again vegetable. When you cut the main head, other smaller heads will grow. The side heads will take a little longer to bolt.


The hot weather effect on broccoli cannot be stopped, but it can be slowed. Growing broccoli in hot weather requires a little extra effort to get a good harvest, but it can be done. The best way to grow broccoli in hot weather is to keep the hot weather from getting to the broccoli roots.

Heather Rhoades
Founder of Gardening Know How

Heather Rhoades founded Gardening Know How in 2007. She holds degrees from Cleveland State University and Northern Kentucky University. She is an avid gardener with a passion for community, and is a recipient of the Master Gardeners of Ohio Lifetime Achievement Award.