Many homeowners treat their lawn like a generic patch of dirt. They grab the first bag on the shelf, ignoring the fact that St. Augustine grass has a specific appetite compared to fescue or rye.
Feeding your yard is a science, not a guessing game. Picking the right nutrient ratio is the secret to a thick, green carpet. These Best St Augustine Fertilizers offer the precise chemistry your grass needs to thrive throughout the year.
Key Takeaways
- Prioritize formulas with high iron content if your main goal is achieving a deep, dark green color.
- Always check the nitrogen ratio to ensure you are promoting leaf growth rather than excessive thatch buildup.
- Select slow-release nitrogen options to prevent fertilizer burn and feed your lawn over an extended period.
- Avoid products with high phosphorus levels unless your soil test specifically indicates a deficiency.
- Match your chosen application method, liquid or granular, to the size of your lawn and your existing equipment.
| Professional Grade Nutrition |  |
SeedRanch St. Augustine 24-2-11 Fertilizer | High nitrogen concentration | Large coverage area | Designed for St. Augustine | View on Amazon | Read Review |
| Instant Color Booster |  |
St. Augustine Liquid Lawn Food | Rapid nutrient absorption | Encourages new runners | Thickens turf density | View on Amazon | Read Review |
| Balanced Iron Supplement |  |
Fertilome 15-0-15 Centipede Lawn Fertilizer | Slow release nitrogen | High iron content | Balanced nutrient profile | View on Amazon | Read Review |
| Versatile Liquid Spray |  |
Simple Lawn Solutions 16-4-8 Fertilizer | Easy to spray | Balanced nutrient ratio | Versatile application | View on Amazon | Read Review |
| Iron Rich Greening |  |
Scotts Green Max Lawn Food | Visible greening results | Includes iron supplement | Easy to spread | View on Amazon | Read Review |
| Reliable General Maintenance |  |
Scotts Turf Builder Lawn Food | Consistent growth results | Improves root strength | Wide compatibility | View on Amazon | Read Review |
| Pest Defense System |  |
Scotts Turf Builder SummerGuard Fertilizer | Dual action protection | Strengthens grass roots | Controls lawn insects | View on Amazon | Read Review |
| Phosphorus Free Efficiency |  |
Sunniland St. Augustine 20-0-6 Fertilizer | Phosphorus free | Slow release nitrogen | Large coverage area | View on Amazon | Read Review |
| Heavy Duty Weedkiller |  |
LESCO St. Augustine Weed Feed | Includes weed control | Professional strength | Large bag size | View on Amazon | Read Review |
| Budget Friendly Greening |  |
St. Augustine 15-0-4 Iron Fertilizer | Includes iron | Phosphorus free | Good value pack | View on Amazon | Read Review |
More Details on Our Top Picks
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SeedRanch St. Augustine 24-2-11 Fertilizer
If you want your yard to grow with the vigor of a summer thunderstorm, this is your best option. The 24-2-11 ratio provides a heavy dose of nitrogen that specifically targets the lush, green requirements of St. Augustine grass.
This is a large 50-pound bag, making it ideal for property owners who manage significant acreage. You should know that because of this high potency, you need to be careful to spread it evenly to avoid burning your lawn.
- Brand:SeedRanch
- Fertilizer Type:Granular
- Nitrogen Ratio:24 percent
- Package Size:50 lbs
- Target Use:St. Augustine grass
- Additional Feature:Promotes rapid growth
- Additional Feature:Formulated for warm seasons
- Additional Feature:Professional density
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St. Augustine Liquid Lawn Food
Liquid applications act like an espresso shot for your grass. This formula is designed to encourage new runners and provide a deep, rich color that granules simply cannot achieve as quickly.
It is perfect for you if you are looking to touch up specific areas or maintain a thick, healthy carpet of grass throughout the growing season. Just keep in mind that liquids require more frequent reapplications than slow-release granular options.
- Fertilizer Type:Liquid
- Package Size:1 Gallon
- Target Use:St. Augustine grass
- Application Method:Spray
- Additional Feature:Promotes rich green color
- Additional Feature:Easy spot treatment
- Additional Feature:Supports lateral growth
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Fertilome 15-0-15 Centipede Lawn Fertilizer
This formula is a reliable workhorse for those who need a balanced NPK ratio. The addition of high iron ensures that your lawn maintains a deep green hue without pushing too much unnecessary vertical growth.
It works effectively for St. Augustine because it uses slow-release nitrogen, which feeds your soil steadily over several weeks. This prevents the common mistake of over-fertilizing your turf.
- Brand:Fertilome
- Fertilizer Type:Granular
- Nitrogen Ratio:15 percent
- Package Size:16 lbs
- Target Use:St. Augustine and Centipede
- Additional Feature:Prevents nutrient spikes
- Additional Feature:Enhances leaf color
- Additional Feature:Steady feeding cycle
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Simple Lawn Solutions 16-4-8 Fertilizer
Versatility is the hallmark of this balanced liquid spray. It functions well as a spring and summer feeding program for almost any grass type, including St. Augustine.
Because it comes in a concentrated form, you can customize the strength to fit your specific lawn condition. It is a smart choice if you prefer avoiding bulky, heavy bags in your garage.
- Brand:Simple Lawn Solutions
- Fertilizer Type:Liquid
- Nitrogen Ratio:16 percent
- Package Size:32 Ounce
- Target Use:All grass types
- Application Method:Spray
- Additional Feature:Concentrated formula
- Additional Feature:Quick soil penetration
- Additional Feature:Good for warm months
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Scotts Green Max Lawn Food
If your lawn looks yellow or tired, this product acts like a tonic for stressed grass. The combination of fertilizer and iron is specifically engineered to bring back a deep, healthy color within days.
It is an excellent choice if you want visible results without the complexity of professional-grade chemical programs. Be aware that the iron content can stain concrete, so you must use caution when applying it near driveways or sidewalks.
- Brand:Scotts
- Fertilizer Type:Granular
- Nitrogen Ratio:27 percent
- Package Size:16.67 lbs
- Target Use:All grass types
- Additional Feature:Covers 5,000 square feet
- Additional Feature:Fast color improvement
- Additional Feature:Dual action formula
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Scotts Turf Builder Lawn Food
Sometimes you just need a standard, high-quality food to keep your lawn fed and happy. This formula provides the essential nutrients your grass needs to withstand the heat of the summer months.
It is the dependable choice for routine care, ensuring that your lawn has the strength to crowd out weeds naturally. It works across all grass types, making it a simple, no-nonsense solution for your shed.
- Brand:Scotts
- Fertilizer Type:Granular
- Package Size:12.5 lbs
- Target Use:All grass types
- Additional Feature:Covers 5,000 square feet
- Additional Feature:Easy granular distribution
- Additional Feature:Trusted lawn food
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Scotts Turf Builder SummerGuard Fertilizer
Summer brings heat and unwanted insects that can destroy your hard work. This product serves double duty by providing necessary nutrition while simultaneously controlling common lawn pests.
It is your best defense if you notice signs of insect damage appearing alongside mid-season stress. Remember that this is a targeted treatment, so it is most effective when you identify the pests before they cause widespread damage.
- Brand:Scotts
- Fertilizer Type:Granular
- Package Size:13.35 lbs
- Target Use:All grass types
- Additional Feature:Includes insect killer
- Additional Feature:Summer heat protection
- Additional Feature:Coverage for 5,000 feet
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Sunniland St. Augustine 20-0-6 Fertilizer
Many soil types already have enough phosphorus, which makes this phosphorus-free formula a environmentally conscious and effective choice. It focuses on the primary needs of St. Augustine grass to drive healthy leaf production.
The slow-release nitrogen ensures your lawn doesn't surge and then crash. It provides a steady, consistent growth rate that makes mowing chores much more predictable.
- Brand:Sunniland
- Fertilizer Type:Granular
- Nitrogen Ratio:20 percent
- Package Size:20 lb Bags (2 Pack)
- Target Use:St. Augustine grass
- Additional Feature:Consistent nutrient release
- Additional Feature:Eco-conscious composition
- Additional Feature:10,000 square feet total
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LESCO St. Augustine Weed Feed
When weeds are actively threatening your lawn, you need a solution with real teeth. This product combines high-quality fertilizer with Penoxsulam, a potent ingredient designed to eliminate tough weeds while feeding your grass.
This is a heavy bag, which indicates it is built for serious turf management. It is best suited for you if you have a significant weed problem that standard food cannot handle.
- Brand:LESCO
- Fertilizer Type:Granular
- Package Size:50 lbs
- Target Use:St. Augustine grass
- Additional Feature:Contains Penoxsulam
- Additional Feature:Targeted weed eradication
- Additional Feature:Long term protection
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St. Augustine 15-0-4 Iron Fertilizer
This formula offers a clean, straightforward way to feed your lawn while adding iron for color. It is a phosphorus-free granular food that caters to the specific dietary requirements of St. Augustine grass.
You get a solid value with the two-pack configuration, covering a total of 8,000 square feet. It is an ideal middle-ground product for homeowners who want professional results without the high cost of premium brands.
- Fertilizer Type:Granular
- Nitrogen Ratio:15 percent
- Package Size:25.6 lb Bags (2 Pack)
- Target Use:St. Augustine grass
- Additional Feature:Covers 8,000 square feet
- Additional Feature:Promotes darker color
- Additional Feature:Consistent granule size
Frequently Asked Questions
How often should I fertilize my St. Augustine grass?
You should feed your lawn every six to eight weeks during the active growing season. Start your first round in the spring once the threat of frost has passed completely. Stop all applications when the grass enters dormancy in the late autumn.
Will fertilizer burn my lawn if I apply too much?
Yes, excessive nitrogen creates a chemical burn that leaves brown, crispy patches across your turf. Always follow the bag rate instructions carefully and avoid overlapping your passes with the spreader. It is better to under-apply and add a light second round later than to scorch your grass with a heavy initial dose.
Should I water after applying fertilizer?
Watering is essential to push the granules off the blades and into the soil root zone. A light irrigation cycle of about a quarter-inch of water helps the nutrients reach their target effectively. This also washes away any dust that could potentially irritate your pets or children if they walk on the lawn immediately.
Can I use a weed-and-feed product on new sod?
Do not use weed-and-feed products on newly installed sod until the roots have fully established, which usually takes at least three months. The herbicides designed to kill weeds can easily damage young, vulnerable grass roots that haven't developed a strong defense yet. Stick to a gentle, nitrogen-rich starter fertilizer during the first season.
Is it better to fertilize before or after mowing?
It is best to fertilize immediately after you finish mowing your lawn. Mowing removes the tips of the grass blades, which allows the nutrients to reach the soil more directly as you spread. This timing also avoids picking up fertilizer granules with your mower deck on your next pass.
