For citrus grower Pete Spyke, the proof of his success with open hydroponics is in the pictures.
The owner of Fort Pierce-based Arapaho Citrus is quick to point to images of his 3-year-old Rock Bottom Grove on the company’s Website, http://www.arapahocitrus.com. Beyond the photos of growing trees are shots of densely packed root balls that Spyke says show one thing: Open hydroponics using drip irrigation promotes fast tree growth without great amounts of water and fertilizer.
And it may be one of the best solutions to citrus greening, also known as huanglongbing or HLB, Spyke says. He views two camps—those who try to live with the disease and those who understand they must live without it.
System helps spur early fruiting
Open hydroponics involves growing citrus on drip irrigation and spoon feeding trees nutrients through the drip. In theory, the system maximizes tree and crop uniformity.
In his 5-acre experimental Rock Bottom Grove, Spyke added an advanced production system that involves high-density plantings of 250 to 400 trees per acre, aggressive psyllid control, intensive pruning, and plant growth and flower set to achieve early fruiting.
Open hydroponics differs from growing trees on micro-jet sprinklers since you have more control over the trees on drip, he says.
“I have plenty of growers growing trees with micro-jets really, really fast, some outgrowing me,” Spyke says. “But what’s happening is it takes them four to six times more water and fertilizer. The point of doing the drip is about control of the trees and it’s about money.”
A young tree with a lean trunk on a micro-jet system spreads roots out evenly over a 12-foot radius, storing fertilizer to use as needed, he says, pointing to photos.
Trees on open hydroponics, on the other hand, have “pots” or root balls that are concentrated under emitters, a strategy that has proven to work best in densely spaced plantings.
Because the roots are concentrated in the wetting zone, nutrient uptake is improved and leaching is reduced, he says.
Growing trees quickly using drip is important, but the main goal is to bring them into fruit production as early as possible before they become infected with the citrus greening bacterium, Spyke says.
“You get them up and into production. And as they get greening, you get them out,” he says. “With drip, I can shift it from vegetative to reproductive. Trees don’t grow fast anymore, and they’re putting all their energy into producing fruit.”