5/30/2025 - By Dr. Tom Reed

Harrell's POLYON® controlled-release fertilizer (CRF) blends have been proven effective in Florida sugarcane production. Producing great yields through efficiency with fewer applications and limiting nutrient loss to the environment has resulted in POLYON® CRF adoption in commercial fields.

POLYON® on Sugarcane Study - Louisiana

Harrell’s wants to see if this efficiency translates to Louisiana. A study was conducted to determine the effects of POLYON® on Louisiana sugarcane production.

The study was in St. Gabriel, LA and was performed in collaboration with Louisiana State University. A single application timing of POLYON® 43-0-0 coated urea at reduced nitrogen rates (N) and 0-0-57 coated muriate of potash (MOP) was evaluated.

The POLYON® applications were compared to a Louisiana grower standard conventional two-application program. The grower standard program utilized urea ammonium nitrate (UAN) and MOP. The trial was on first ratoon L01-299 cultivar, a promising new sugarcane cultivar for Louisiana production, and had four treatments that utilized POLYON® controlled-release fertilizer (CRF) (Table 1). Fertilizer applications were made in April.

Normalized Difference Vegetation Index (NDVI) was used to quantify vegetation greenness and give an understanding of vegetation density. Plant health had similar ratings with half the N applied with the POLYON® CRF treatments (Figure 1).

The reduction in nitrogen applied, and potentially lost to environment, compared to traditional practices demonstrates POLYON® efficiency. As seen in table 2 below, POLYON® treatments with reduced N rates yielded equal to grower standard practice with half the N applied (Table 2).

The trial produced a much greater yield than historical production in the area at high quality. The reduced rate N POLYON® program with MOP removing an application can fit into production at current fertilizer costs, especially with a greater yield than the historical average. Based on the data, utilizing POLYON® potassium sources and N resulted in the greatest sugar quantity and quality, and may further increase plant vigor and yield. However, this might not be economically beneficial. This study is being repeated this year along with an additional trial comparing POLYON® products to reduced conventional rates.

Learn More from Your Harrell’s Rep

Harrell’s is continually evaluating fertilizer blends for yield and nutrient efficiency optimization. Harrell's POLYON® blends are engineered to provide nutrients over time at predictable rates under specified conditions. If you’d like to learn more about POLYON® and how it can help your operation, reach out to your Harrell's Rep today.