When to Fertilize St. Augustine Grass in Florida

Some Florida lawns do not need phosphorous.

Depending on the results of soil analysis, fertilization of St. Augustine grass is recommended in two to six applications from spring through fall. Frequency of fertilization is determined in part by the level of maintenance desired by the homeowner.

North Florida

Untimely fertilization results in water pollution.

High maintenance St. Augustine lawns are fertilized with a complete nitrogen, phosphorous and potassium (NPK) fertilizer in March and September; with iron in June; and a slow-release form of nitrogen in May and June.

Moderate maintenance lawns are fertilized with a complete NPK fertilizer in March and September; a slow-release form of nitrogen in May; and iron in June.

Low maintenance lawns are fertilized with a complete NPK fertilizer in March and September, and iron in June.

Central Florida

Timely fertilization increases resilience to pests and diseases.

High maintenance St. Augustine lawns receive a complete nitrogen, phosphorous and potassium (NPK) fertilizer in February and October; nitrogen in April; nitrogen in slow-release form in May and April; and iron in July.

Moderate maintenance lawns receive a complete NPK fertilizer in March, September and October; iron in July; and nitrogen in slow-release form in May and August.

Low maintenance lawns receive a complete NPK fertilizer in March and September, and iron in July.

South Florida

Grass clippings provide nitrogen to Florida lawns.

High maintenance St. Augustine lawns are fertilized with a complete nitrogen, phosphorous and potassium (NPK) fertilizer in February and November; nitrogen in April; and a slow-release form of nitrogen in May, July and September.

Moderate maintenance lawns are fertilized with a complete NPK fertilizer in February and November; nitrogen in April; and a slow-release form of nitrogen in June and August.

Low maintenance lawns are fertilized with a complete NPK fertilizer in March and October, and a slow-release form of nitrogen in May and July.

References

• "The Florida Lawn Handbook;" Laurie Trenholm and J. Bryan Unruh; 2005
• University of Florida Extension: St. Augustinegrass for Florida Lawns

Resources

• American-Lawns dot com: Grasses