Expert Advises: Ease Up On Fertilizers, Exotics

Many people use way more fertilizer than is necessary for their lawns and landscaping, when often none at all is needed, according to Dr. Ron Rice of the University of Florida’s Palm Beach County Cooperative Extension Service, who spoke at the Loxahatchee Groves Landowners’ Association meeting Thursday, Aug. 22.

Rice said Florida landscapers are required to take a course on best management practices in order to work, and he advised that residents who do their own lawn care educate themselves as to how much fertilizer is necessary.

Rice, whose office is in Belle Glade, has spent the past 15 years working primarily with sugar cane and rice growers on best management practices. He spoke about green industries and landscapers who take care of homeowners’ yards.

Up until now, landscaping businesses have gone largely unregulated, he said.

“Pretty much anybody can put together a little business and go out and mow something, apply something and who knows what else,” Rice said. “Take that and expand across the entire state, and you’ve got a potential disaster just building up over time in terms of fertilizer influence.”

In many cases, fertilizer is being applied when the plants can’t use it, and the nutrients go down through highly leachable soils, particularly during the rainy season.

“You have all these nutrients going into our water systems, and this sort of thing builds up,” he said. “Once it builds up, it takes a long time to build back down.”

The Florida Department of Environmental Protection, the University of Florida and green industry leaders have put together a training course for best management practices that is soon to become enacted as law.

“People don’t just go to this training for fun,” he said. “They go to this training to get a certification. The certification is required by law Jan. 1, 2014. Anybody who applies fertilizer or any kind of inputs like herbicides, pesticides and insecticides, they have to have this certification, otherwise it’s going to be illegal.”

Fertilizers are anything that promotes plant growth, which includes adjusting acidity or alkalinity. “We happen to be in a high pH zone,” Rice said. “We have a lot of calcium carbonate in our soil.”

Urban soils are very unpredictable, which lead to people adding all sorts of additives to the ground.

“Who knows what they are?” he said. “Urban soils are really disturbed and destroyed, so we typically have to care for them some way with inputs. One of the inputs might be some sort of sulfur to acidify a soil that is high-pH. Lots of areas where it’s acidic, not in this area, but in the Panhandle, you’ll apply lime and calcium carbonate to bring the pH up.”

The issue with landscapers is that they are generally responding to clients’ wishes rather than the overall good of the ecosystem, he said, adding that landscapers are being taught to educate their clients to accept some things and reject others.

“It’s not like we have to have this perfect Palm Beach island-type of landscape around our homes,” Rice said. “It just takes way too much management. It’s just not sustainable to keep exotic plants, lots of them, growing all the time. You might have little clusters of them, but to have them scattered all over the place, it’s a disaster waiting to happen.”

Fertilizers are used to increase growth or improve the appearance.

“You might want to green things up, you might want to make a bloom more beautiful, encourage more flowering,” he said. “This is the reason why we add nutrients.”

Rice stressed that there are beautiful trees and plants that simply don’t do well in Florida’s climate.

“Just stop,” he said. “Trying to keep some of these trees alive and healthy over a long period of time is just a headache, and you just wind up damaging the environment without really realizing it.”

There are certain times of the year when application of nutrients is not good, such as in winter when the grass is not growing, he said. “Physiologically, the plant does not want to take up nutrients,” he said. “It’s just sort of sitting there waiting for the warm weather. As you get into spring and summer during the growth period, that’s when you should have a fertilizer program. Coming down to October with a big hit of nitrogen and phosphorus and potassium is just useless.”

Applying fertilizer when it is known that particularly rainy weather is coming is also a waste because it will just be washed away, he said.

“One problem is that right now, the industry is driven by contract,” Rice said. “They go to those homeowners every month and they have to do something. They have to apply something because this is a package they sell. We have to get away from that. That’s part of this training we’re trying to get across to people.”

Another pointless application is pre-sodding fertilizer, he said.

“The sod has just been ripped out of the ground,” Rice said. “The roots are all shattered. They are physiologically unable to do anything, so there is no point in putting this down and then putting fertilizer on top. It’s a waste of time and money. Wait at least 30 to 60 days. Roots will start growing, and will then begin to take up fertilizer.”

There is no point in targeting trees in lawns unless they have an obvious nutrient deficiency. “Otherwise the tree is going to be OK,” Rice said, explaining that the trees will pick up nutrients that leach down from the lawn turf.

He advised that homeowners get nutrient analyses of their lawns, sometimes from different areas that seem to have different growth patterns.

“The industry is supposed to take soil tests and get it interpreted correctly by a lab that knows what they’re doing,” he said. “The most important thing to look for is pH because pH will be a driver, especially in micronutrient availability.”

The West Palm Beach office of the Cooperative Extension Service has soil test kits available, he said.

“Get a couple of places that are representative of what you’d like to understand, mix it up and put it in a bag and send it to the lab, and in three or four weeks you’ll have an answer,” Rice said.

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ABOVE: Dr. Ron Rice of the University of Florida’s Palm Beach County Cooperative Extension Service speaks at last week’s LGLA meeting.