Getting On Board With BMPs

Jack Putnal and his son, Riley, manage Putnal Farms in southern Suwannee County. The Putnals farm peanuts, watermelon, corn, iron clay peas, millet, and cattle. Jack and Riley are known for their high-quality watermelons harvested beginning in late May and ending in late June or early July.


The next-generation Putnal, Riley, has been given more and more of the leadership in growing the watermelon crop in recent years. Riley has embraced the technology available to refine his water and nutrient management program. The 2008 watermelon season ended as one of the best ever for the Putnals; however, the season started with the disappointment of losing several acres of young transplants to hard freezes in March. Even in the face of killing frosts, Riley wanted to learn a key piece of information on those cold nights: Does it pay to run the drip irrigation system overnight to protect the crop?

Professional Assistance

Mace Bauer, UF/IFAS best management practices (BMP) implementation team leader, and Bob Hochmuth, UF/IFAS Extension agent, set up a study during two different freeze events using recording thermometers and a data logger to record temperatures continuously throughout the night. The data showed there was no benefit to running the drip system as a means of freeze protection. This was a very important piece of information to save water usage and reduce leaching losses of fertilizer.

Tools Of The Trade

Riley Putnal has also used two other key BMP tools available through the Suwannee River Partnership Cost Share program. Those two tools are Cardy plant sap meters to measure nitrogen and potassium in the field and TDR portable soil moisture probes. Hochmuth has been working with Riley for the past few years to help him gain the confidence in using these tools on his own.

“Very few growers have mastered the plant sap meters quite like Riley,” says Hochmuth.

Samples are pulled at least weekly during the season, and the results are used to adjust the amount of nitrogen and potassium to fertigate using the UF/IFAS recommendations as the guide. In addition, the soil moisture probe is used routinely, several times weekly to guide the irrigation program to assure adequate water supply and also minimize the risk of leaching. The Putnals also use other methods to assist in the overall BMP program, including: automatic-switching irrigation valves, GPS light-bar guidance system, nurse tanks for safe pesticide tank filling, and early field scouting for pest and disease detection.

Lower Costs, Higher Yields

The Putnals have saved money on water and fertilizer by using the Partnership BMP tools in their watermelon and other crops. At the same time, they indicated the 2008 watermelon crop was “the highest yielding ever” on their farm.

In Riley’s spare time, he and his wife Renata enjoy raising their young twin daughters, Brooke and Britney.

Special thanks to Helena for sponsoring the printing of Florida BMP Guides. E-mail [email protected] for copies of the guide.