Best St Augustine Grass Fertilizer for a Lush, Healthy Lawn
St Augustine lawn care hinges on balanced nutrients, steady feeding, and weed management tailored to warm-season grasses. The right fertilizer supports deep root growth, vibrant color, and resilience against heat and drought. This guide reviews five top options designed for St Augustine lawns, highlighting nutrient blends, coverage, and application timing. From granular blends to organic formulas and liquid feeds, these selections cover spring and summer needs while offering practical guidance on usage, safety, and performance. Use the table below to compare core details at a glance.
| Product | Brand | Type | Coverage / Size | Key Benefit |
|---|---|---|---|---|
| Sunniland Weed & Feed 20-0-6 | Generic | Granular Weed & Feed | 5000 sq ft | Easy to spread; spring and fall applications |
| SeedRanch St. Augustine Lawn 24-2-11 | Lesco | Granular Fertilizer | 50 Lbs | Includes 6% Iron for greening; broad coverage |
| LESCO 50 lb St Augustine Grass Weed & Feed | LESCO | Granular Weed & Feed | 13,000 sq ft | 17-0-17; slow-release up to 8 weeks; Floratam-safe |
| Organic Plant Magic – Truly Organic Slow Release | Organic Plant Magic | Granular Organic | 20 Lb | GroBiotics; kid/pet-safe; broad lawn use |
| Emerald 10-0-20 Lawn Fertilizer | Lawn Synergy | Granular | 25 lb | Iron + NuTrace micronutrients; strong color, steady feeding |
Sunniland Weed & Feed 20-0-6 Lawn Fertilizer
This Sunniland formulation provides a balanced 20-0-6 NPK mix designed for St Augustine lawns. It combines fertilizer nutrition with broadleaf weed control, helping lawns stay green while suppressing common weeds. The product is described as easy to spread and easy to handle, with two applications recommended in spring and fall. Its compatibility with all St Augustine grass varieties makes it a versatile option for warm-season lawns. For best results, apply according to label directions and water lightly after application if soil conditions allow.
- Easy to spread granules
- Two applications per year (spring and fall)
- Suitable for all St Augustine grass types
SeedRanch St. Augustine Lawn 24-2-11
SeedRanch St. Augustine Lawn 24-2-11 is a granular formula designed to support St Augustine turf with a balanced 24-2-11 NPK blend. A notable feature is the inclusion of iron to promote rich greening, contributing to a more vibrant lawn color. The product covers up to 12,000 sq ft, making it suitable for medium to larger yards. It provides essential nutrients for St Augustine lawns and supports steady growth throughout the growing season. Apply according to package instructions for best results and water after application if needed.
- Includes 6% Iron for greening
- 12,000 sq ft coverage
- Provides nutrients for St Augustine lawns
LESCO 50 lb St Augustine Grass Weed & Feed
LESCO’s 50-pound weed-and-feed blend for St Augustine turf features a 17-0-17 NPK ratio with slow-release properties that extend feeding up to about eight weeks. The formulation includes Penoxsulam and is designed for use on St Augustine varieties, including Floratam. It’s recommended to apply when the turf is wet and allow it to dry before irrigation or mowing. With a coverage around 13,000 sq ft, this product targets both fertilization and weed suppression, delivering a practical option for larger lawns needing weed control alongside nutrition.
- Slow-release fertilizer coverage up to 8 weeks
- Penoxsulam herbicide included
- Safe for Floratam variety
Organic Plant Magic Truly Organic Slow Release Fertilizer
Organic Plant Magic offers a truly organic slow-release lawn fertilizer designed for all-purpose lawn care, including St Augustine. The product is described as alive with GroBiotics—amino and humic acids plus beneficial biology—supporting soil health and nutrient uptake. It emphasizes safety for kids, pets, and the environment, aligning with eco-conscious lawn care. The granular formula provides gradual feeding suitable for steady growth and sustainable greening across a variety of lawn types beyond St Augustine.
- GroBiotics with amino and humic acids
- Safe for kids, pets, and environment
- All-purpose lawn use
Emerald 10-0-20 Lawn Fertilizer
Emerald 10-0-20 is a high-nitrogen option designed to deliver a deep green color with controlled growth. The formula includes iron and NuTrace micronutrients to promote a bold, dark green lawn without excessive top growth. Its 45% slow-release nitrogen via AccuBlu technology helps provide a steady feed for up to eight weeks, reducing waste. The potassium-rich 10-0-20 mix supports drought tolerance, disease resistance, and root strength, making it suitable for warm-season lawns such as St Augustine in challenging climates.
- Iron and NuTrace micronutrients for color
- 45% slow-release nitrogen for steady feeding
- 10-0-20 balance supports stress tolerance
Buying Guide
Key factors to consider
Choose a product whose NPK ratio matches your lawn’s needs and climate. For St Augustine, higher nitrogen promotes green color and growth, while balanced phosphorus and potassium support root health and drought resistance. Consider whether you want a granular, liquid, or organic option based on your preferred application method and environmental concerns.
Nitrogen source and release
Slow-release formulations provide longer feeding with fewer application events, reducing the risk of burn and nutrient waste. Quick-release blends deliver faster results but may require more frequent applications. For warm-season grasses, a mix of slow-release nitrogen and micronutrients (iron, zinc) often yields the best color and resilience.
Weed control vs. pure fertilization
Weed-and-feed products save time by combining weed suppression with feeding. However, they may require precise timing to avoid harming new or stressed turf. If you only need nutrition, select a fertilizer without herbicides and apply weed control separately as needed.
Coverage, size, and yard scale
Match product coverage to your lawn size. Larger yards benefit from higher coverage per bag or container, reducing the frequency of purchases. Ensure the product’s coverage aligns with your square footage and plan accordingly for gradual, even application.
Safety and environment
Organic formulas emphasize kid- and pet-safety and environmental considerations. If you have children or pets, you may prefer organic or slow-release products with lower risk of runoff. Always follow label directions and store products securely.
Application timing and weather
Apply during appropriate seasons when the lawn is actively growing and soil temperatures support nutrient uptake. Avoid applying during extreme heat or drought, and water as directed after application to help with distribution and root absorption.
Practical recommendations
For a balanced approach, pair a granular fertilizer with a separate weed-control plan if weed pressure is high. For eco-conscious lawns, consider organic options like Organic Plant Magic. For color and rapid greening, products with iron plus slow-release nitrogen, such as Emerald, can be effective. Always tailor your choice to your local climate, lawn conditions, and maintenance routine.