Cool weather crops for the vegetable garden

By Jean Thomson


Spring weather thus far has generally proved to be cool indeed ? too cool even for some of the cool-loving vegetable plants. However, it is a good time to be thinking about planting possibilities so that we can seize the opportunities that may arise.

Cole crops such as broccoli and cabbage grow best in daytime temperatures between 60 and 70 degrees. While they do not flourish in the heat of midsummer, they also should not be planted when temperatures stay below 50 degrees. If planted then, they may produce heads prematurely, a process known as buttoning. Unfortunately, plants that button do not produce usable heads.

Typically, we in southern Iowa can plant cole crops in early April. Gardeners who have not started their seeds indoors can look for stocky transplants at garden centers. Be sure to harden plants in a protected location and gradually give them more sunlight before actual planting.

Cole crops like moist but well-drained garden soil in full sun. Space them 18 to 24 inches apart in the ground or in raised beds.

After the plants are in, feed each one with one to two pints of a starter fertilizer solution. Prepare this by dissolving two tablespoons of 10-10-10 fertilizer in a gallon of water.

Our ISU extension horticulturists recommend specific cultivars that do well in Iowa. For broccoli, look for ?Arcadia,? ?Goliath,? ?Green Magic,? ?Gypsy,? ?Imperial,? and ?Packman.?

Recommended varieties of green cabbage include ?Blue Vantage,? ?Early Thunder,? ?Quick Start,? ?Stonehead,? and ?Thunderhead.?

Red cabbage recommendations include ?Red Jewel,? ?Ruby Ball Improved,? and ?Ruby Perfection.?

If you are looking for savoy cabbage, try ?Savoy Ace Improved,? ?Savoy Blue,? and ?Savoy King.?

CAUTIONARY NOTE: When you head to garden centers and big box stores, stay mindful of where you garden and the conditions that your place presents! The first offering of plants that I personally spotted included lavender, a plant that likes cool, dry summers. To me, that does not sound like a typical Iowa summer! Sometimes it is fun to take a chance, but overall cautious buying is likely to yield better results.