While high-density plantings are getting a lot of coverage, the results of plant density trials advise growers to find the “sweet spot.”

In Griffin Fertilizer’s latest column in Central Florida Ag News, I shared the results of plant density trials going on at the Indian River Research and Education Center. High-density plantings are getting a lot of press as growers stay profitable in the era of citrus greening; some growers are trying plant densities higher than 900 trees per acre. While packing as many trees as possible into an acre may seem the most desirable way to go, the research being led by Assistant Professor of Citrus Horticulture, Dr. Rhuanito Soranz Ferrarezi, at the Indian River Research and Education Center shows that growers should aim for the “sweet spot” for their chosen rootstock/scion that will be grown. See the details below.

Plant Density Trials and the “Sweet Spot”

Two year-long trials at Indian River looked at the production of trees planted at 119 trees per acre, 173 trees per acre, or 393 trees per acre. According to Ferrarezi, both trials found that a higher tree planting density increases fruit yield and fruit quality. However, the highest end of the high-density plantings had a yield that was too low due to poor rootstock performance/choice, according to Ferrarezi.

This brings up the concept of the “sweet spot,” which is the planting density point where spacing will be optimal for each different scion/rootstock combination to achieve maximum production. Ferrarezi points out research that shows that, despite efforts like pruning, citrus trees will strive to maintain their natural forms. For instance, scion/rootstock combinations that are meant to grow to a large size will continue to attempt to do so at the cost of fruit production.

Essentially, any grower looking into high-density plantings should do his or her homework to find the optimal planting density—the “sweet spot”—rather than trying to get as high a density as possible.

Griffin Fertilizer is committed to helping both growers and ranchers make sound agronomic and economic decisions in order to maximize the health of their grove and pasture. As a full-service custom dry & liquid fertilizer blender and crop protection product distributor, we will continue our mission to further advance Florida agriculture. For questions or concerns about your farm or pasture, contact us and one of our team will be in touch.