For the past three years, Frank Hester has grown cabbage instead of tobacco, starting with 10 acres and working his way up to 25.

That much acreage is unheard of in Vance County, where cabbage is a relatively unfamiliar commodity and production expertise is scarce. But after six harvests — a spring and a fall crop each year — Hester has met his challenges successfully and remains committed to his choice.

“When I first started out, I focused primarily on how I would market the crop, harvest it and store it,” Hester said, “but as I gradually increased acreage, growth problems demanded my attention. I wanted to blame the weather, but by the third season, I could see that sporadic, uneven growth was a recurring issue.”

When cabbage heads do not grow at a uniform rate, it takes multiple passes through a field over several weeks to harvest them as they mature. This process is inefficient and time-consuming.

Hester wrestled with the problem and found that, because cabbage had such a short window of maturity, adjusting its fertility was more difficult than with traditional field crops.

During the 2011 fall season, Hester noticed that one out of every five cabbages was not “sizing up.” He asked local agricultural experts for advice and got two tips right away.

First, submit soil and plant tissue samples to identify any nutrient problems.

Second, contact regional agronomist Kent Yarborough with the N.C. Department of Agriculture and Consumer Services.

The department’s Agronomic Services Division analyzes agricultural samples for plant nutrient content and other properties that affect crop production. Division scientists review laboratory results and provide recommendations to correct problems.

Regional agronomists with the division work directly with growers to make sure they know how to take samples, interpret report data and implement recommendations. Because agronomists cover several counties, they become familiar with a wide range of crops.

“I sent in some samples before Kent came out to look at my crop,” Hester said, “but when he got here he focused on areas of poor growth and took more samples.”

Said Yarborough: “The primary goal on my first visit was to show Mr. Hester the step-by-step process involved in troubleshooting a nutrient problem . . . the strategy behind sampling. I wanted him to see that it is very important to take both soil and tissue samples separately from areas of good growth and areas of poor growth.

“Then you can compare and contrast test results in a meaningful way that isn’t possible if your sample represents an average of the entire field in general.” 

Showed clear differences

In Hester’s case, agronomic test results showed clear differences between “good” and “poor” areas.

Cabbage is a high-value crop that has special micronutrient needs, particularly boron and molybdenum, Yarborough said. “Boron turned out to be one concern,” he said.

“Report results for the problem areas indicated low soil pH, high salt values and boron-deficient plants. Some other nutrients were low, but not deficient, in both the ‘good’ and the ‘poor’ areas. These included potassium, calcium and the micronutrient molybdenum.”

Hester had been fertilizing his crop with a complete fertilizer that already contained micronutrients. He was expecting this product to provide his crop’s entire nutrient need.

But each cabbage crop needs about 2 pounds of boron per acre, and his fertilizer supplied only a quarter-pound. To correct this, Yarborough suggested a foliar application of a liquid boron product right away.

Spurred by Yarborough’s advice, Hester decided to take a similar approach in addressing the low levels of molybdenum. “Foliar application of molybdenum is good insurance,” Hester said. “It is inexpensive, probably about $3 an acre, and it produces a good benefit. I already know I’m going to use it, but by tissue testing, I can find out whether I need two or three applications.”

The long-term solution to many of these nutrient problems is to lime the soils regularly to bring the pH up to an acceptable level of 6.0. Hester began this process in January, but it takes several months for soil pH to change.

This spring he used tissue testing to monitor nutrient levels and determine whether additional fertilizer was needed.

“Cabbage is only a 75- to 80-day crop,” Hester said. “I don’t want to miss a crucial application of nutrients.”

Hester and Yarborough have worked out a fertilization strategy for the crop. Cabbage uses 140 to 150 total units of nitrogen and about 110 units of phosphate and potash over the course of a season.

At planting, Hester’s goal is to apply 50 units of nitrogen, phosphate and potash. Three or four weeks later, he will apply standard 17-17-17, then top-dress at about six weeks with 13-0-14. He will continue to add boron and molybdenum as a foliar spray throughout the season in conjunction with routine insecticide applications.

This attention to detail paid off this spring. Hester’s yields rebounded. He harvested 15 percent more than his first season and 20 percent more than last fall. In fact, the yield was his best to date.

“Growing cabbage has been new for me,” Hester said. “Where I had weak areas, Kent helped me out. His advice has turned my yields around.”

Like Hester, all North Carolina growers have access to the services of the NCDA&CS Agronomic Services Division and its 13 regional agronomists throughout the state. Contact information for these advisers is available online at www.ncagr.gov/agronomi/rahome.htm.