Bahiagrass (Paspalum notatum) is a resilient, warm-season turf, prized for its deep root system and tolerance of sandy, infertile soils. While it requires less maintenance than many other turf varieties, its health depends significantly on precise fertilization timing. The unique sub-tropical climate and local environmental regulations in Florida make knowing when to apply nutrients the most important factor for a successful bahiagrass lawn.
Preparing for the Growing Season
The growing season begins when the grass emerges from its winter dormancy. This transition is triggered by rising soil temperatures, not just the calendar date. Bahiagrass begins active growth when the soil consistently reaches 65°F to 70°F.
Applying fertilizer too early, particularly in North and Central Florida, risks stimulating new growth that a late-season frost could damage. Before the first application, a soil test provides a baseline for existing nutrient levels and pH, preventing unnecessary applications. Adjusting the mower height to two to three inches at the start of the season also helps encourage deeper root development and greater stress tolerance.
The Florida Fertilization Schedule
The active growth period for bahiagrass generally supports two to four fertilizer applications between spring green-up and fall. The first feeding is typically scheduled for mid-to-late spring (early April in Central Florida and mid-April further north) once the threat of cold weather has passed. This initial application supports the grass as it breaks dormancy and prepares for the summer heat.
A second application may occur in early summer (June or July) to sustain growth during the hottest months, which is when bahiagrass produces its most significant biomass. However, this timing is often constrained by local environmental ordinances that impose summer application restrictions. Homeowners in South Florida, where growth can occur year-round, may have more flexibility in scheduling applications.
The final application should be completed in early fall, usually around September, to help the turf store carbohydrates for winter dormancy. Fertilizing too late, after the grass’s growth has naturally slowed, is inefficient and wastes nutrients. Consistent timing based on the turf’s biological needs, rather than just the calendar, maximizes nutrient uptake and overall lawn health.
Selecting the Proper Nutrients
The specific nutrient content is as important as the timing. For bahiagrass, nitrogen (N) is necessary for green color and blade growth, but it should be supplied using a product containing at least 50% slow-release nitrogen. Slow-release formulations provide a steady supply of nutrients over several weeks, helping avoid excessive growth flushes and minimizing the risk of nutrient runoff, especially in Florida’s sandy soils.
Phosphorus (P) is often unnecessary for established lawns because many Florida soils naturally contain sufficient levels. Unnecessary phosphorus application is discouraged due to its potential environmental impact. State rule 5E-1.003 mandates that application rates cannot exceed one pound of nitrogen per 1,000 square feet per application.
Potassium (K) is beneficial for improving the grass’s resistance to drought, heat, and disease, making it a valuable component in a fertilizer blend. An application of an iron source can also help address chlorosis (yellowing), which occurs when bahiagrass struggles to take up iron in high-pH soils.
Navigating Local Ordinances
Fertilizer application in Florida is subject to unique legal constraints designed to protect water quality. Many counties and municipalities enforce a fertilizer blackout period that typically runs from June 1 through September 30. During this time, the application of fertilizers containing nitrogen and phosphorus is prohibited, coinciding with the heavy summer rainy season when runoff is most likely.
These restrictions prevent nutrient pollution that can lead to harmful algal blooms in local waterways. Homeowners are also required to maintain a mandatory setback, generally 10 to 15 feet, from any water body (lakes, rivers, or retention ponds) where fertilizer application is permanently prohibited. Because these rules can vary significantly by county or municipality, checking local ordinances is necessary to ensure compliance and avoid potential fines.