During my recent speaking engagements with industry I have been asking for a show of hands to see how many people are doing business in areas that are currently impacted by fertilizer restrictions of some sort. Only 30 percent or so raised their hands. My response was “Just wait.”
Pinellas County passed a ban on fertilizer applications during the “summer rainy season” which has been identified as anytime from the beginning of June through the end of September.
I have long been an advocate of responsible fertilizer application and would argue that you can not find a more environmentally responsible set of people than those that work in the landscape industry. I respect the goal of ordinances like this, but feel that they missed the mark. The ban effectively limits application of fertilizers to turf during the warmest months of the year – the time of year when the warm-season grasses are actively growing and need nutrition to produce a healthy stand of turfgrass.
Turfgrasses play a VERY important role in the landscape. No, I am not talking about aesthetics. Turf plays a critical role in the landscape by stabilizing slopes, preventing soil erosion, and providing an evaporative cooling effect that reduces the temperature of the surrounding environment. There are no better plants in the landscape to prevent soil erosion than healthy grasses. They have a dense, finely textured root system and a dense canopy, all characteristics that encourage water infiltration and limit runoff.
Some argue that native plants can do the same job without the need for fertilizers. Unfortunately, the urban landscape is not a native landscape. Every time a new neighborhood is planned, the first step is to come in with large equipment and remove all of the topsoil, which is often sold to the highest bidder. After completing construction, the builders will grade the property, and if you are lucky, they will move in two to three inches of topsoil on top of the compacted subsoil and sand that surrounds the new homes. It is no surprise that many plants that are native to Florida are not able to survive in the harsh soil environment that we have in urban areas.
If turfgrasses are NOT fertilized, they begin to decline in health. The canopy density begins to thin out increasing the risk of soil erosion while also increasing weed pressure. From the perspective of protecting the environment, this is not a good situation. By not maintaining the health of the turf we have increased the risk of water pollution during rainfall/runoff events and have indirectly increased the potential use of herbicides which will be used to control the weeds which may have otherwise not been able to take hold in the dense, healthy stand of turf.
That brings us back to the ban which prevents the application of fertilizers to warm-season grasses during the summer. As a result of the ban, fertilizers will have to be applied during the spring/fall/winter months. The grasses will not be actively growing and will not have the same extensive root system that would be present during the summer. This is going to increase the risk of nutrient leaching. If we simply managed the turf the way numerous researchers have suggested we would reduce the risk of runoff AND leaching.
You probably can guess that I do not agree with banning fertilizer applications on warm-season turfgrasses during the summer months. The fact remains that much of the nutrient leaching and runoff pollution is thought to come from non-point sources. This means that we do not know where exactly it is coming from, only that it is there. I am not saying that fertilizer applications in the urban environment are never a problem. Irresponsible applications are definitely a problem. If you are applying fertilizer to the lawn, sidewalk, street, and driveway without cleaning it up, you should be banned from ever purchasing/applying another ounce of fertilizer. If you have such a complete disregard for the environment you should not be allowed to manage any portion of the landscape, regardless of whether or not you own it.