AMES, Iowa — Cole crops is the general term used to describe broccoli, Brussels sprouts, cabbage, cauliflower, collards, kale and kohlrabi. Harvesting vegetables at the right stage of maturity results in nutritious, high quality produce. Horticulturists with Iowa State University Extension and Outreach tell when to harvest broccoli, cabbage and cauliflower. To have additional questions answered, contact Hortline at hortline@iastate.edu or 515-294-3108.
When can I harvest cabbage?
The harvest of cabbage may begin when the heads are firm and the size of a softball. Mature cabbage should be harvested when the heads are solid and tight, before they crack or split. Splitting is caused by excessive water uptake; the resulting pressure splits the head. Splitting of mature heads may be prevented by pulling plants upward and gently twisting. Some of the roots will be broken, thereby reducing water uptake.
Cabbage may be placed in a perforated plastic bag and stored in the refrigerator for two to four weeks. Cabbage may be stored up to three to four months when placed in a cool (32 degrees Fahrenheit), moist (95% to 100% relative humidity) location, such as a root cellar.
When should I harvest broccoli?
Broccoli should be harvested when the head is fully developed, but before the small yellow flower buds start to open. At harvest, the terminal head should be tight, blue-green and approximately 6 to 7 inches in diameter. Cut the central stem just below the head. Many cultivars will produce several small side heads (about 1 to 3 inches across) in the axils of the leaves after the central head has been removed.
Broccoli may be placed in a perforated plastic bag and stored in the refrigerator for up to 10 to 14 days.
When should I harvest cauliflower?
Cauliflower should be harvested when the heads are smooth, firm and compact. Full-sized heads may be 6 to 8 inches across. Over-mature heads will begin to open up and become grainy in texture and appearance.
Cauliflower may be placed in perforated plastic bags and stored in the refrigerator for up to two weeks.
— Richard Jauron and Willy Klein, Iowa State University Extension and Outreach
For more news from Iowa, click here.