By MADDY ROHR
K-State Research and Extension News Service
MANHATTAN — Cole crops planted in the spring need to mature before summer heat arrives, which means a fertilizer boost is necessary, said Kansas State University horticulture expert Ward Upham.
Cole crops are cool-season vegetables and include cabbage, broccoli, and cauliflower.
“They must grow quickly while the weather is cool,” Upham said. “A side dressing of fertilizer about three weeks after transplanting helps plants continue to grow rapidly.”
Upham suggests fertilizers high in nitrogen. “Do not use lawn fertilizers that have weed killers or preventers,” he said.
Upham said a nitrate of soda or blood meal at the rate of 1/3 cup per 10 feet of row is ideal.
“You may also use lawn fertilizers that have close to 30 percent nitrogen such as a 30-3-4 or 29-5-4 but the rate should be cut in half to three tablespoons per 10 feet of row,” Upham said.
If it doesn’t rain, fertilizer must be watered in.
Upham and his colleagues in K-State's Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens. The newsletter is available to view online or can be delivered by email each week.
Interested persons can also send their garden and yard-related questions to Upham at [email protected], or contact your local K-State Research and Extension office.