The sun beats down on your lawn, turning once-vibrant blades into thin, yellowish strands that lose their lush appeal. You want that thick, carpet-like turf back, but picking the right nourishment feels like guessing a password. Finding the Best Fertilizers for St Augustine requires knowing exactly what your soil craves.
Getting the right balance of nutrients turns a patch of struggle into a source of pride. You can cultivate a dense, resilient lawn if you stick to the correct formulas. Keep reading to see which solutions provide the most effective support for your grass.
Key Takeaways
- Prioritize formulas with high nitrogen content to encourage rapid leaf growth and a deep green appearance.
- Check the NPK ratio on the bag, as St. Augustine grasses thrive when these three primary nutrients are carefully balanced for your soil type.
- Apply granular products with a slow-release nitrogen component to avoid burning the roots while providing sustained feeding throughout the season.
- Select products containing iron supplements if your primary goal is to correct yellowing or achieve a darker shade of green.
- Verify whether the product contains pre-emergent or post-emergent herbicides to ensure you do not inadvertently damage your grass while targeting weeds.
| Best Spot Treatment |  |
Scotts EZ Patch Lawn Repair | Combines mulch and fertilizer | Easy spot repair | Promotes quick growth | View on Amazon | Read Review |
| Versatile Liquid Feed |  |
Simple Lawn Solutions Balanced Liquid | Quick absorption rate | Versatile for any grass | Easy sprayer attachment | View on Amazon | Read Review |
| Growth Stimulant Specialist |  |
St. Augustine Liquid Lawn Food | Encourages new runners | Promotes rich green color | Easy to apply | View on Amazon | Read Review |
| Sustained Nutrient Supply |  |
Fertilome 15-0-15 Slow Release | Slow release nitrogen | High iron content | Prevents nutrient burn | View on Amazon | Read Review |
| Heavy Duty Bulk |  |
SeedRanch St. Augustine Fertilizer | High nitrogen count | Bulk packaging | Promotes rapid growth | View on Amazon | Read Review |
| Iron Rich Greening |  |
Scotts Green Max Food | Rapid greening results | Added iron supplement | Consistent coverage area | View on Amazon | Read Review |
| All Purpose Standard |  |
Scotts Turf Builder Lawn Food | Reliable, balanced formula | Works for all grass | Easy to spread | View on Amazon | Read Review |
| Dual Action Defense |  |
Scotts SummerGuard Insect Control | Fertilizes and kills bugs | Summer stress management | Covers large areas | View on Amazon | Read Review |
| Rapid Growth Sprayer |  |
Simple Lawn Solutions High Nitrogen | Very high nitrogen | Convenient attached sprayer | Quick absorption | View on Amazon | Read Review |
| Total Lawn Maintenance |  |
Fertilome Weed and Feed | Weed and feed combo | Includes pre-emergent control | Specifically formulated for St. Augustine | View on Amazon | Read Review |
More Details on Our Top Picks
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Scotts EZ Patch Lawn Repair
If your yard has stubborn bare patches, this combination of mulch and fertilizer is your best friend. It acts like a healing bandage for your grass, providing the necessary nutrients and coverage to help St. Augustine fill back in quickly.
It works well for minor damage, but you should look elsewhere for feeding your entire lawn. This is strictly a targeted repair tool for specific trouble spots.
- Brand Name:Scotts
- Package Weight:3.75 lbs (2 pack)
- Coverage Area:170 sq ft
- Additional Feature:Includes mulch for moisture
- Additional Feature:Designed for patch repair
- Additional Feature:Simple application process
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Simple Lawn Solutions Balanced Liquid
This liquid formula is a balanced 16-4-8 mix, which makes it a solid choice if you want consistent growth throughout the spring and summer. It absorbs quickly, providing your grass with an immediate nutrient boost that avoids the wait time associated with granular products.
But because it is a liquid, you will need to apply it more frequently than slow-release options. It is an excellent choice for those who prefer spraying their lawn rather than spreading heavy bags of fertilizer.
- Brand Name:Simple Lawn Solutions
- Formula Type:Liquid concentrate
- NPK Ratio:16-4-8
- Package Weight:32 ounces
- Additional Feature:Concentrated liquid formula
- Additional Feature:Works for all grasses
- Additional Feature:Spring and summer use
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St. Augustine Liquid Lawn Food
When your grass is looking thin or lacks that deep green color, this concentrated liquid can help turn things around. It focuses on encouraging new runners, which is the primary way St. Augustine grass spreads across your lawn.
It comes in a smaller container, so it is better suited for targeted treatment or smaller lawns rather than large acreages. Use it when you need a concentrated shot of nutrition to revitalize a tired lawn.
- Brand Name:Generic/Specialty
- Formula Type:Liquid lawn food
- Package Weight:8 oz
- Additional Feature:Boosts grass thickness
- Additional Feature:Ideal for runners
- Additional Feature:Rapid color enhancement
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Fertilome 15-0-15 Slow Release
This formula is an excellent choice if you want to feed your lawn without worrying about burning the grass. The slow-release nitrogen provides a steady supply of nutrients over time, which creates a more even growth pattern.
The added iron helps ensure that your grass maintains a deep, healthy color throughout the season. It is a reliable, professional-grade option for homeowners who prefer a set-it-and-forget-it approach to lawn care.
- Brand Name:Fertilome
- Formula Type:Granular
- NPK Ratio:15-0-15
- Package Weight:16 lbs
- Additional Feature:Safe for warm-season grasses
- Additional Feature:Sustained feeding cycle
- Additional Feature:Professional grade formula
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SeedRanch St. Augustine Fertilizer
If you have a large lawn and want to minimize trips to the store, this 50-pound bag is the way to go. The high nitrogen ratio of 24-2-11 packs a serious punch, encouraging rapid growth and dense coverage across your property.
It is a powerful formula, so be sure to follow your spreader settings to avoid over-application. This is a value-driven choice for those managing significant square footage who need effective, high-nitrogen feeding.
- Brand Name:SeedRanch
- Formula Type:Granular
- NPK Ratio:24-2-11
- Package Weight:50 lbs
- Additional Feature:Large capacity bag
- Additional Feature:High-nitrogen blend
- Additional Feature:Suitable for large lawns
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Scotts Green Max Food
Sometimes your grass is growing fine but just looks a bit dull, and that is where this iron-heavy formula shines. It is designed to green up your lawn in as little as three days, acting like a cosmetic upgrade for your turf.
While it is great for color, it does not offer the same level of growth stimulation as high-nitrogen alternatives. Think of this as your go-to color enhancer when you want your yard to pop for a weekend gathering.
- Brand Name:Scotts
- Formula Type:Granular
- Package Weight:16.67 lbs
- Coverage Area:5,000 sq ft
- Additional Feature:Fast color improvement
- Additional Feature:Iron-fortified formula
- Additional Feature:Visible results quickly
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Scotts Turf Builder Lawn Food
When you want a reliable, widely available fertilizer that works on just about any grass type, this is the classic choice. It provides a balanced diet for your lawn, helping to build stronger roots and more resilient grass blades over time.
It is simple to use and fits into almost any seasonal feeding schedule. This is the dependable baseline product for homeowners who want to keep their lawn healthy without overcomplicating their routine.
- Brand Name:Scotts
- Formula Type:Granular
- Package Weight:12.5 lbs
- Coverage Area:5,000 sq ft
- Additional Feature:Strengthens grass roots
- Additional Feature:Simple application routine
- Additional Feature:Consistent nutrient delivery
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Scotts SummerGuard Insect Control
Summer heat often brings out the bugs, and this product solves two problems at once by feeding your lawn while providing insect control. It is a smart, time-saving solution for anyone dealing with common lawn pests that thrive in warm weather.
Because it handles both jobs, it is slightly more complex to apply than a standard fertilizer. You should use this when you suspect that bugs are damaging your turf along with the usual mid-summer stress.
- Brand Name:Scotts
- Formula Type:Granular
- Package Weight:13.35 lbs
- Coverage Area:5,000 sq ft
- Additional Feature:Integrated insect killer
- Additional Feature:Protects against damage
- Additional Feature:Seasonal pest management
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Simple Lawn Solutions High Nitrogen
This is a high-nitrogen liquid that is meant to force growth during the peak of the season. The 28-0-0 ratio is designed for quick absorption, giving your grass the raw fuel it needs to thicken up in a hurry.
It comes with an attached sprayer, which makes it incredibly simple to treat your lawn without needing a separate machine. Just keep in mind that such a high nitrogen level means you must apply it evenly to avoid green streaks.
- Brand Name:Simple Lawn Solutions
- Formula Type:Liquid
- NPK Ratio:28-0-0
- Package Weight:32 ounces
- Additional Feature:Rapid growth formula
- Additional Feature:Ready to spray
- Additional Feature:Quick and slow release
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Fertilome Weed and Feed
If you are tired of battling weeds while trying to feed your grass, this granulated weed and feed is a massive help. It uses Atrazine to stop weeds from appearing while giving your St. Augustine the nutrients it needs to thrive.
You have to be careful with timing, as this is a powerful chemical treatment. Use this for a comprehensive seasonal cleanup rather than as a casual, frequent feeding option.
- Brand Name:Fertilome
- Formula Type:Granular
- NPK Ratio:15-0-4
- Package Weight:25.6 lbs
- Additional Feature:Atrazine weed control
- Additional Feature:Safe for warm-season grass
- Additional Feature:Dual action treatment
Frequently Asked Questions
How often should I fertilize my St. Augustine grass?
You should apply fertilizer every six to eight weeks during the active growing season. Start your first application in early spring once the danger of frost has passed. Stop feeding about six weeks before the first expected frost date in your area.
Will high nitrogen levels hurt my lawn in the summer?
Excess nitrogen during peak heat can lead to rapid, succulent growth that attracts pests and disease. Stick to a moderate application rate during the hottest months of July and August. If the weather is dry, make sure you water the lawn thoroughly after applying to avoid burning the roots.
Do I really need to water after applying fertilizer?
Yes, watering is essential to help the nutrients move into the soil where the roots can actually reach them. Aim for about one-quarter inch of water immediately after spreading the granules. This also helps wash any dust off the leaf blades, which keeps the grass from getting burned.
Can I use a general-purpose lawn fertilizer?
You have to be extremely cautious, as many general fertilizers contain chemicals like Atrazine that can be toxic to St. Augustine. Always check the ingredient list on the back of the bag. If the label does not specifically list St. Augustine as a compatible grass, leave it on the shelf.
Why does my lawn still look thin after fertilizing?
Fertilizer is only one piece of the puzzle, as St. Augustine also requires proper sunlight and deep, infrequent watering. If you have dense shade or poor soil compaction, the grass will struggle regardless of the nutrients you provide. Check your soil pH to ensure it sits between 6.0 and 7.5, which is the sweet spot for nutrient absorption.
