FOR IMMEDIATE RELEASE
FRIDAY, AUG. 26, 2005
||Catherine Stokes, information and communication specialist
NCDA&CS Agronomic Division
Blueberry fertilization gets a closer look
WHITE LAKE — You've heard the saying "when one door closes, another opens." That adage is proving itself true over and over again as many tobacco farmers seek alternative crops to tobacco.
One of the contenders — blueberries – has seen a more than 66 percent increase in production since 2001, prompting the N.C. Department of Agriculture and Consumer Services to study the crop's nutrient needs so it can offer better advice on fertilizer rates and application.
Today there are about 6,000 acres of commercial blueberries in North Carolina, and 80 percent are in Bladen County. The water table there is high, the soil pH is low, and the blueberries thrive. However, Rick Morris, the NCDA&CS regional agronomist with responsibilities for Bladen, thinks there may be room for improvement.
Last January while attending a blueberry growers’ meeting, Morris heard about problems with uneven growth and speculation about the effects of nutrients on pollination and fruit quality. He was surprised to discover that, for the most part, blueberry growers were not using state agronomic services such as soil testing and plant tissue analysis. "There are about 4,000 acres of blueberries in Bladen County," Morris said, "but the NCDA&CS agronomic laboratory received only 17 soil samples and 13 tissue samples from these acres during 2004. Growers of any high-dollar cash crop really should be using agronomic testing. It is one of the best ways to improve crop quality and minimize costs."
Blueberries have unique requirements. They thrive in acid or low pH soils that are unsuitable for many plants. They have shallow root systems and grow best in soils with a high water table. This set of circumstances may explain why most blueberry producers have not felt the need for agronomic testing.
Liming is not an issue, and they have relied on a standard, "one-size-fits-all" fertilizer application strategy. This approach has yielded some success, but Morris sees an opportunity to raise the bar.
"We can't assume that soils are uniform throughout all fields," Morris said. "I can walk through a field and see obvious differences in organic matter, and there are probably other differences that are not as noticeable. I don't know that anyone has looked into the status of micronutrients in these soils. Soil testing and tissue analysis can tell growers exactly which nutrients their crops need."
With 27 years of experience in agriculture, Morris has seen the benefits that agronomic testing can provide in traditional row crops, strawberries, vegetables and ornamentals. He wants blueberry growers to have that same edge. His first step has been to initiate a field study with the help of Bladen blueberry grower Henson Barnes.
"Mr. Barnes is a very progressive blueberry farmer," Morris said. "He uses color and softness sorters to select the best berries, and he's trying to harvest more of his acreage mechanically. He's very interested in the possible benefits of additional potassium and micronutrients."
This spring Morris and Barnes began a replicated field test that they plan to continue next year. The test evaluates the addition of potassium to the standard fertilization strategy most growers already use. The test also compares the effectiveness of liquid versus dry fertilizers. Plant tissue samples are taken monthly to monitor plant nutrient uptake in each treatment.
"I'd like to use liquid fertilizer," said Barnes, "but there has not been a whole lot of study on it. I like the idea of accurate placement — that you can put the fertilizer right where you want it. I also think it would be easier to apply."
As far as the need for specific nutrients, Barnes would like to verify some of his theories. He has been putting out extra potassium for three years because he heard it would make the plants more attractive to the bees that pollinate them. He would also like to know if some of the growth differences he sees are due to nutrient problems. He hopes the study will shed some light on these questions.
"I think blueberry farmers would be willing to put out additional nutrients," Barnes said, "once they see that it can help."
Morris agrees. "Soil testing and plant tissue analysis give growers valuable information on the nutrient status of the soil and the plant — information that can make their fertilization program more cost-effective and efficient. I would like to see more blueberry growers using these tests and reaping the benefits."
North Carolinians have access to one of the most comprehensive agronomic testing and advisory services in the nation. The laboratories of the NCDA&CS Agronomic Division perform soil tests, measure nutrient levels within plant tissue, identify plant-parasitic nematodes and analyze the nutrient content of composted materials and animal wastes to be used as fertilizer. In addition, the lab tests water and nutrient solutions for nutrient content and other chemical properties relevant to plant growth.
To support these testing services, 13 regional agronomists are available throughout the state to visit growers; evaluate suspected nutrient problems; give advice on sampling, liming and fertilization; and help identify and manage nematode problems. Visit the Agronomic Division’s Field Services Section to find contact information for the NCDA&CS regional agronomist assigned to your area.
Agronomist Rick Morris is available to provide advice on fertilization, nutrient management or nematode problems in Bladen, Brunswick, Columbus, Cumberland and Robeson counties. He can be reached by phone at (910) 866-5485 or by e-mail.