Florida-Friendly Landscaping™ Principle # 3:

Fertilize Appropriately

“Greening up” our communities does not mean applying a hefty dose of fertilizers to our landscapes. Quite the contrary! Fertilizers can be hazardous to the health of your yard and the environment when they are misused. Frequently people don’t realize that many landscape plants demand little or no fertilizer once they are established and mature.

In fact, when over-applied, fertilizers aggravate insect and disease problems and force excessive growth which must be mowed or pruned. Excess fertilizers can run off yards into waterways or leach into aquifers, polluting drinking water. Fertilizing appropriately if at all is the key to living green!

The Fertilizer Label

Florida law requires that fertilizer manufacturers supply a label with every bag of fertilizer.

There's a wealth of information on the label once you understand how to interpret it. To demystify much of the information you will find on the label, please see: The Florida Fertilizer Label.

Use fertilizers in which at least 15% of the nitrogen is in a slow- or controlled-release form.

Fertilizer Facts

• Fertilizer is not plant food. Food to a plant is the sugars it makes through photosynthesis. Fertilizer nutrients are used in this process, but a lawn or plant growing poorly in too much shade will not grow better if fertilized.
• The Truth about "100% Organic." The "100% Organic" claim often refers only to the nitrogen in the bag. Furthermore, the nitrogen can be derived from natural products such as manure or it can be from synthetic chemicals such as urea. Read the label to determine where the "organic" nitrogen is coming from.
• Buy nutrients, not fertilizer. Many fertilizers contain a number of plant nutrients even though only one or two may be needed. What plant response do you want - greener growth? More flowers or fruits? Know which nutrients will provide these responses and buy only those.

Slow-Release Fertilizers

When fertilizer nutrients are in "slow-release" forms, they are available to plants over a longer period of time, and less nutrients are wasted or lost as pollutants. Look for these terms on the product or fertilizer tag:

Timed-release, slow-release, or controlled-release.

Water insoluble nitrogen, activated sludge, sulfur-coated urea (SCU), IBDU, ureaform (UF), nitroform, or polymer-, plastic-, or resin-coated urea.

Florida-Friendly Landscapes: Fertilize Appropriately

• Fertilize only as needed to maintain the health of lawns and landscape plants. If plants show signs of stress, such as yellow leaves or stunted growth, identify the problem before applying fertilizer. Do not exceed the rate of 1 pound of nitrogen per 1,000 square feet per application.
• Use slow-release fertilizers. Buy fertilizers that contain at least 15% of the nitrogen in slow- release forms.
• Use iron (ferrous sulfate or chelated iron) instead of nitrogen to make your lawn green during the summer.

For more information on fertilizer recommendations for landscape plants,
please see: Landscape Fertilization.