St. Lucie County’s summer fertilizer blackout runs through Sept. 30. For a Port St. Lucie lawn, Oct. 1 is the time to consider fertilizing again—but not to give the lawn company an open-ended go-ahead. Check the product and the conditions before anything goes on the grass.
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The blackout covers your Port St. Lucie lawn
St. Lucie County prohibits fertilizer containing nitrogen or phosphorus during the June 1 to Sept. 30 blackout. The county says the ordinance applies countywide, including Port St. Lucie, Florida. A lawn company doing the work does not put your yard outside the rule.
Once the blackout ends, the seasonal prohibition no longer blocks a nitrogen application. The other fertilizer rules still matter. Northern-house logic—wait for the calendar to turn, then spread whatever is in the bag—does not work here. Oct. 1 changes the seasonal restriction; it does not cancel the product requirements or the restrictions tied to rain and storms.
What to check before an Oct. 1 application
St. Lucie County’s guidance says fertilizer applications starting Oct. 1 must use a product with at least 50% slow-release nitrogen and no phosphorus unless a soil test shows a deficiency. That applies whether you spread it yourself or arrange for someone else to do the job.
- Check that the fertilizer has at least 50% slow-release nitrogen.
- Check that it has no phosphorus unless a soil test shows a deficiency.
- Check conditions before the planned application, rather than treating Oct. 1 as an automatic appointment.
Those checks belong together. A product that meets the slow-release requirement does not get a pass on phosphorus, and a suitable product does not get a pass on application conditions. If the plan includes phosphorus, get the soil-test result that shows the need before it is applied. Otherwise, the straightforward plan is fertilizer without phosphorus.
Hold the fertilizer before storms or heavy rain
Even outside the summer blackout, St. Lucie County says nitrogen or phosphorus fertilizer cannot be applied when the National Weather Service has issued a flood, tropical storm or hurricane watch or warning for any portion of the county, or when heavy rain is expected. The county also says not to apply fertilizer containing nitrogen or phosphorus when soils are saturated…