Florida Friendly Fertilizing Tips and Guidelines
Recent studies have shown that nitrate levels are rising in many local water bodies. Nitrate is a form of nitrogen that is found in inorganic fertilizers. Nitrogen is needed to help lawns stay healthy. When fertilizer is applied correctly, the grass will use all the nitrogen. If applied incorrectly, nitrogen can leach into our groundwater or wash off the land and into lakes, rivers and the gulf. Once in our water bodies, nutrients from fertilizer may cause algae to grow. Algae can form large blooms that shade out beneficial aquatic plants and use oxygen that fish need to survive.
You can help protect water quality and have a beautiful lawn by following the Florida-friendly fertilizing guidelines* outlined in this booklet. Check with your local city or county to see if your area has a more restrictive fertilizer ordinance. Visit Florida-Friendly Fertilizing for detailed information on fertilizing for your grass species, your location in the state and your desired level of lawn care.
Fertilizing appropriately is one of the nine Florida-Friendly Landscaping TM principles — a set of guidelines that help protect natural resources while having a beautiful landscape. For more information, visit Florida-Friendly Landscaping
* Guidelines established by the University of Florida’s Institute of Food and Agricultural Sciences(UF/IFAS) and the Florida Department of Environmental Protection (FDEP).
Why Fertilize Your Lawn?
Fertilizers are designed to make your lawn green, healthy and more stress-tolerant. To maintain health, turfgrass needs nutrients, some of which are supplied by your soil. In some cases, fertilizer is necessary because your soil cannot supply the grass with all the nutrients it needs to stay healthy and green over the years. When needed, fertilizer should be applied according to UF/IFAS and FDEP guidelines. If applied correctly, fertilizer can help your lawn stay healthy by:
TIP: If your landscape is healthy and its appearance is pleasing, you may not need to fertilize the entire site, only problem areas. Take samples of problem areas to your local Extension office to check for pests and pH deficiencies.
Step 1 - Getting Ready To Fertilize
Test Your Soil
A good approach to proper fertilization is to start with a soil test. Many Florida soils are naturally high in phosphorus, one of three major nutrients in fertilizer. If your soil test shows an adequate level of phosphorus, choose a fertilizer blend that does not contain it. Your soil test will also tell you about your soil’s pH (acidity or alkalinity) levels and other nutrient levels. You can get information on obtaining a soil test from your county Extension office or visit WaterMatters.org/yards.
Know When to Apply Fertilizer
To prevent fertilizer from washing into water bodies, it’s important to know the right time to fertilize. Follow these tips before fertilizing:
Step 2 - Determining How Much To Buy
To avoid storing leftover fertilizer, decide how much you need before you make a purchase. Don’t guess! Measure your property and calculate the total square footage of turfgrass. Do not include landscape plants in the area to be fertilized.
Step 3 - Selecting Fertilizer
Read the Label
All fertilizer labels have three bold numbers. The first number on the label represents nitrogen, the second number represents phosphorus and the third number represents potassium. These are the three major nutrients your lawn needs to thrive.
In general, select a fertilizer where the first and third numbers on the label are equal or in a 2:1 ratio and the middle number is zero or as low as possible.
Look for a fertilizer where the ratio of nitrogen to phosphorus (the first to second number) is a minimum of 4 to 1. For example, a 12-3-10 and a 15-0-15 fertilizer would follow this recommendation.
Most home lawn fertilizers contain some slow-release nitrogen. It takes longer for your yard to benefit from slow-release nitrogen, but the effects will last longer. Many of these fertilizers provide fertilization for 60 days or longer, depending on environmental conditions. As a result, fewer nutrients may be wasted or lost as pollutants.
To find a slow-release fertilizer, look for these terms on the product or fertilizer tag for nitrogen:
Tips for Newly Planted Turf
Labeling Requirements Rule
The Florida Department of Agriculture and Consumer Services passed a rule regulating labeling requirements in the state for urban turf fertilizers. The new labeling requirements will make it easier for homeowners to find lawn fertilizers with both slow-release nitrogen and low phosphorus. This rule is intended to reduce potential pollution that might result from application of excess fertilizer to lawns.
TIP: Do not over-fertilize. Repeatedly using large amounts of nitrogen fertilizer can increase pests and environmental stress problems.
Step 4 - Applying Fertilizer
When applying fertilizer, the most important thing to remember is to read and follow the instructions on the fertilizer bag. Proper application will ensure maximum coverage, resulting in a healthy lawn while protecting water bodies.
Calculate Application Rates
To determine the correct amount of fertilizer per 1,000 square feet, divide 100 by the percentage of nitrogen in the bag. For example, a fertilizer with a 15-0-15 label contains 15% nitrogen, 0% phosphorus and 15% potassium. Divide 100 by 15 to get 6.6; this is the number of pounds of slow-release fertilizer needed to apply one pound of nitrogen per 1,000 square feet. This works for any fertilizer product or amount of nitrogen.
Nitrogen application rates vary according to type of turf and location in the state. Please visit WaterMatters.org/fertilizing for more information on calculating application rates.
Apply Using a Spreader
Water-in your fertilizer after application with no more than 1/4 inch of water. To determine how much this is, perform a catch-can test. Do this by placing empty cat food or tuna cans around the perimeter of your sprinkler or irrigation system and time how long it takes to fill them to this depth (1/4 inch). Do this before fertilizing so that you know how long to run the system. This will put the nutrients at root level, where they can be taken up most efficiently. Watering-in with more water than 1/4 inch can result in fertilizer leaching more rapidly through the soil.
TIP: Use only the amount of fertilizer that is recommended. More is NOT better.
Sweep up fertilizer spills and put back in bag.
Leave a 10-foot no-pesticide, no-fertilizer zone between the fertilized area and a water body.
Step 5 - Maintaining A Healthy Lawn
Proper lawn maintenance is vital for the long-term health of your lawn. Appropriate mowing and watering practices must occur so your lawn will have a healthy root system, be more drought-tolerant and be able to resist pests and disease.
Irrigation System Tips
More lawns are damaged by improper irrigation practices than by any other practice. Take control of your automatic irrigation system using these tips:
Seasonal Watering Tips
Regardless of the season, grass needs no more than 1/2 to 3/4 inch of water each time you irrigate. Irrigation frequency will vary by location, soil type, amount of shade, temperature and other lawn characteristics and stresses.
All the tips and guidelines in a handy PDF. Also, include diagrams and other pictures.