Best Lawn Fertilizers for St. Augustine Grass to Promote Healthy Growth 2025
Keeping your St. Augustine lawn vibrant and healthy requires the right fertilizer tailored to its specific needs. St. Augustine grass thrives in warm climates and benefits from balanced nutrients that support its dense, lush growth. To help you select the optimal product, here’s a summary table of top fertilizers designed especially for St. Augustine grass, highlighting their key features and coverage.
| Product | Key Features | Coverage | Brand |
|---|---|---|---|
| SeedRanch St. Augustine Lawn 24-2-11 Fertilizer | 6% Iron for greening, nutrient-rich, slow-release formula | 12,000 sq. ft. | Lesco |
| LESCO St. Augustine Grass Weed and Feed with Penoxsulam | Weed control, slow release, safe for Floratam variety | 13,000 sq. ft. | LESCO |
| Advanced 16-4-8 Liquid Fertilizer by Simple Lawn Solutions | Complete NPK, seaweed & fish nutrients, easy spray application | Versatile use, any lawn size | Simple Lawn Solutions |
| Scotts Turf Builder Southern Lawn Fertilizer | All-in-One particles, builds root strength, heat & drought protection | 5,000 sq. ft. | Scotts |
| Scotts Green Max Lawn Food with Iron | Iron supplement for fast greening, dual-action formula | 5,000 sq. ft. | Scotts |
SeedRanch St. Augustine Lawn 24-2-11 Fertilizer
This fertilizer features a 24-2-11 NPK ratio enriched with 6% iron, which is vital for deep greening and lush lawn appearance. Its formulation is specifically designed for St. Augustine grass, promoting strong growth while covering up to 12,000 square feet. The inclusion of iron enhances chlorophyll production, ensuring your lawn maintains a rich green color. This product provides steady nutrient release to keep your turf healthy throughout the growing season.
LESCO 50 lb. St. Augustine Grass Weed and Feed with Penoxsulam
This professional-grade fertilizer combines a 17-0-17 nutrient blend with a weed control formula featuring Penoxsulam, offering a dual-action treatment tailored for St. Augustine lawns, including the Floratam variety. It covers 13,000 square feet and utilizes a slow-release mechanism that feeds grass over 8 weeks. Application is best done on wet turf for optimal absorption. This product offers effective weed suppression alongside fertilization for healthier grass development.
Advanced 16-4-8 Balanced NPK Liquid Fertilizer from Simple Lawn Solutions
This liquid fertilizer offers a balanced 16-4-8 NPK ratio with added seaweed and fish emulsion to deliver vital macronutrients easily absorbed by any grass type, including St. Augustine. Its spray applicator allows for uniform coverage and immediate nourishment. This formula stimulates rapid greening and vigorous growth, suitable for spring and summer applications, making it a versatile choice for maintaining a lush lawn.
Scotts Turf Builder Southern Lawn Fertilizer
Specifically formulated for southern grasses like St. Augustine, this fertilizer contains Scotts’ proprietary All-in-One particles that enhance root development, enabling grass to withstand heat and drought stress effectively. Covering up to 5,000 square feet, it supports strong turf and can be applied on wet or dry lawns during the growing season for convenience and efficient results.
Scotts Green Max Lawn Food with Iron Supplement
This dual-action fertilizer features a balanced nutrient profile enhanced with 5% iron to deliver rich, fast greening visible in as little as 3 days. Effective on all grass types including St. Augustine, it’s designed for application throughout spring, summer, or fall. The iron supplement enhances chlorophyll production, providing lasting color and overall lawn vitality.
Buying Guide for St. Augustine Lawn Fertilizer
Choosing the best fertilizer for your St. Augustine lawn involves considering several factors to ensure optimal growth and sustainability:
Nutrient Composition (NPK Ratio)
St. Augustine grass thrives with a balanced supply of nitrogen (N), phosphorus (P), and potassium (K). Nitrogen encourages green leafy growth, phosphorus supports root development, and potassium improves resilience against drought and disease. A nutrient ratio such as 24-2-11 or 16-4-8 is effective, but ensure the fertilizer fits your lawn’s current growth stage and soil condition.
Iron Content
Iron is essential for enhancing the vibrant green color of St. Augustine grass. Fertilizers containing 5-6% iron are beneficial for rapid greening and improving turf density. If deep color is a priority, look for products that specifically list iron content.
Slow-Release vs. Liquid Fertilizers
- Slow-release fertilizers provide nutrients over an extended period, reducing the frequency of applications and minimizing nutrient runoff.
- Liquid fertilizers offer faster nutrient absorption and are ideal for quick greening or spot treatments but may require more frequent application.
Weed Control Integration
Some fertilizers include herbicides to manage common southern lawn weeds. If weed prevention is a priority, consider a weed-and-feed product that controls perennial weeds like dandelions and clover while feeding your grass.
Application Coverage and Frequency
Consider the size of your lawn and how often you are prepared to fertilize. Products covering large areas and offering extended feeding periods reduce maintenance efforts. Follow manufacturer instructions carefully on application timing, especially regarding soil moisture and temperature conditions for best results.
Grass Type Compatibility
Ensure the fertilizer is formulated specifically for St. Augustine grass or southern lawns to maximize nutrient availability and avoid damage. Some products are safe for sensitive varieties like Floratam, which is important if you have this type in your lawn.
By assessing these factors, you can select a fertilizer that best suits your St. Augustine lawn’s needs, promoting strong, vibrant turf throughout the growing season.