Implementing the Five Rs of Nutrient Stewardship for Fertigation in Florida’s Vegetable Production

Diagram of root zone fertilized with drip fertigation (left) and dry granular fertilization with drip irrigation (right). This diagram illustrates how a fertigation system is able to confine nutrients to the root zone. Because the nutrients are supplied with irrigation and in small quantities, they are less likely to leach and more likely to be taken up by the crop. Conversely, granular fertilization supplies the soil with a larger quantity of nutrients at one time, thereby enhancing the likelihood of leaching. Credits: Mary Dixon, UF/IFAS

The five Rs of nutrient stewardship is a mnemonic device used to emphasize accuracy and precision for nutrient management so as to apply the (1) right source of fertilizer at the (2) right rate at the (3) right time in the (4) right place with the (5) right irrigation. Because the majority of Florida’s soils are sandy, this fifth R is imperative for sustainable nutrient management for commercial crop production. These main points of nutrient management (source, rate, time, place, irrigation) may help enhance sustainability by reducing pollution by eutrophication, nitrogen loss through ammonia volatilization, and climate change from soil greenhouse gas emission. This new 8-page publication of the UF/IFAS Horticultural Sciences Department was written by Mary Dixon and Guodong Liu.

Implementing the Four Rs (4Rs) in Nutrient Stewardship for Tomato Production

Freshly picked tomatoes.Fertilization plays a critical role in tomato production across the state of Florida. However, appropriate fertilization management depends on four major components (4Rs): right source, right rate, right placement, and right timing. Farming practices that follow the 4Rs can provide nutrients for optimal tomato productivity while minimizing the risk of nutrient losses and adverse environmental effects, both of which are important to the development of agricultural sustainability. This 6-page fact sheet discusses the 4Rs as well as conventional dry source fertilizers, controlled-release or slow-release source fertilizers, and liquid source fertilizers. Written by Qingren Wang, Guodong Liu, Kelly Morgan, and Yuncong Li, and published by the UF Department of Horticultural Sciences, October 2015.