Economic Benefits Of Controlled-Release Fertilizers In Northern Florida Tomatoes

Tomato growers in North Florida may be able to save time, cut costs, and increase profits by using controlled-release nitrogen fertilizers, according to a new study released by researchers from the University of Florida. Our work used tomatoes as the specific test crop but is applicable to all vegetable production regions in the coastal plain sands using raised beds, and drip irrigation under plastic mulch.

For growers facing rising input costs, tight margins, and limited labor availability,

evaluating both conventional and alternative N fertilizers has become critical for understanding total production costs and profitability. Although fertilizer applications are meant to help reduce marketable yield variability in fresh-market vegetable production, climatic conditions on biomass production are difficult to predict.

The study tested how different nitrogen fertilizer strategies affect tomato yield, quality, and overall profitability programs. By reducing the number of applications (CRFs) release nutrients gradually over the growing season, reducing the need for multiple fertilizer applications and lowering the risk of nutrient loss. In fact, a single preplant application at the full N rate has the potential to replace multiple in-season fertigations.

Controlled-release fertilizers maintained or even improved tomato yields compared to traditional fertilizer programs. By reducing the number of applications, CRFs can save growers both labor and fertilizer costs. This approach allows growers to increase profits while minimizing nutrient runoff, helping to protect local waterways.

For growers facing rising input costs and tight margins, CRFs offer a practical strategy to make tomato production more efficient, profitable, and environmentally responsible.

According to lead author Laura Jalpa, “Our team was motivated by the need to identify

nitrogen management strategies that are practical for growers, economically sound, and

environmentally sustainable. Rising fertilizer costs, limited labor, and water quality

concerns made controlled-release fertilizers an important solution to evaluate.”

This research was conducted by Laura Jalpa under the supervision of Dr. Rao S.

Mylavarapu, with contributions from Tara Wade, George Hochmuth, Yuncong Li, and

Bala Rathinasabapathi at the University of Florida.

Dr. Mylavarapu is a Professor and Director at the University of Florida IFAS Analytical Services Laboratories. The Sustainable Nutrients Systems Lab of Dr. Mylavarapu focuses on improvements in applied nitrogen and phosphorus use efficiencies by major crops produced in Florida. Identifying tools for field management of applied N and P using 4Rs principles is emphasized, for implementation as Best Nutrient Management Practices for agronomic and environmental sustainability.

The full article can be found on the ASHS HortTechnology electronic journal website at: https://doi.org/10.21273/HORTTECH05623-25

About The American Society for Horticultural Science
Established in 1903, the American Society for Horticultural Science is recognized around the world as one of the most respected and influential professional societies for horticultural scientists. ASHS is committed to promoting and encouraging national and international interest in scientific research and education in all branches of horticulture.

Comprised of thousands of members worldwide, ASHS represents a broad cross-section of the horticultural community - scientists, educators, students, landscape and turf managers, government, extension agents and industry professionals. ASHS members focus on practices and problems in horticulture: breeding, propagation, production and management, harvesting, handling and storage, processing, marketing and use of horticultural plants and products. For more information, visit ashs.org.