While one part of the citrus research industry is looking for ways to develop HLB-resistant trees in order to maximizing yield, another part is focused on the configuration of the groves themselves.
With start-up and maintenance costs rising for growers, it may be time to look at the bigger picture — and make things a little smaller.
Traditional growing practices held that wider space between trees and between rows helped keep trees producing at a high level.
Now, thanks to research by UF/IFAS citrus economist Dr. Ariel Singerman, an assistant professor at the Lake Alfred Citrus Research and Education, growers can have “spacing options” that puts trees closer together in a much higher density in order to maximize the total number of fruit produced per acre. These “high-density groves” have shown promise in Singerman’s research.
“Planting higher-density groves could offset some of the impact of HLB by decreasing the cost of production per box, due to costs being allocated to a higher number of boxes,” says Singerman. “This could contribute to an increase in profitability per acre.”
In a study that explored the relationship between input costs, prices, yield and planting density, Singerman and his team analyzed Valencia oranges at three different densities: 145 trees per acre — which is approximately the statewide density average — 220 trees per acre and 303 trees per acre. The results showed that higher density groves yield more fruit per acre than those with lower densities.
Studies have also examined how to place the trees, instead of planting in a straight line using a triangular staggered configuration, in order to maximize space. Some of these configurations also cut cost on irrigation and fertilization costs.
While high-density groves seems promising, Singerman is quick to stress that going to a high-density model is not a “one size fits all” solution. In order to help growers assess the strengths and weaknesses of the diverse number of planting densities, he has developed a customizable spreadsheet as a guide.
“We tell growers to customize the spreadsheet using their input costs to figure out what planting density is most beneficial, says Singerman. “Every operation is different.”
The spreadsheet is available free of charge at: https://crec.ifas.ufl.edu/extension/economics/pdf/Summary_of_incentive_programs.pdf