St. Augustine grass is prized for its lush, tropical appearance and ability to thrive in warm, humid southern climates. Selecting the right best fertilizer for St Augustine ensures your lawn develops dense, weed-resistant turf with that iconic deep green color.
This warm-season grass has specific nutritional requirements that differ from other turf types, with nitrogen being the primary driver for growth and color. Understanding soil conditions, growth patterns, and seasonal needs helps match the right fertilizer formulation to your St. Augustine lawn.
Quality fertilizer for St. Augustine promotes vigorous stolon development, thick canopy coverage, and improved stress tolerance that keeps your lawn looking its best. Choosing appropriate formulations prevents common issues like excessive thatch buildup, nutrient deficiencies, or fungal diseases that plague this grass type.
In this guide, we will review the top 10 fertilizers ideally suited for St. Augustine grass, evaluating their nutrient ratios, release patterns, and overall performance. We will also provide essential application guidance to ensure your St. Augustine lawn achieves that coveted lush, green appearance.
Top 10 Best Fertilizer For St Augustine
1. Scotts Turf Builder Southern Lawn Food 32-0-4 – Best high-nitrogen fertilizer for St Augustine
Scotts Turf Builder Southern Lawn Food delivers a powerful 32-0-4 NPK formulation designed specifically for warm-season grasses like St. Augustine. This high-nitrogen blend promotes rapid green-up and aggressive stolon growth while the elevated potassium supports root strength and drought tolerance. The inclusion of 2% iron provides an additional greening boost, making lawns appear noticeably darker and healthier within days.
- SOUTHERN GRASS FERTILIZER: Scotts Turf Builder Southern Lawn Food is a pesticide-free lawn fertilizer specially formulated for Southern lawns
- WHEN TO APPLY: Apply this fertilizer for grass during the growing season in spring, summer, or fall; for fast results, lightly water in after application
The slow-release nitrogen technology ensures consistent feeding for up to eight weeks, preventing the feast-or-famine growth cycles that plague quick-release formulations. This extended feeding window reduces application frequency while maintaining steady, even growth that eliminates unsightly growth surges. The formula works effectively across all St. Augustine varieties, making it a versatile choice for most homeowners.
Apply this product to damp grass and water thoroughly to activate the nutrients for optimal absorption. The 5,000-square-foot coverage per bag provides excellent value for medium-sized lawns requiring consistent nutrition. For homeowners seeking rapid greening with sustained results, Scotts Turf Builder delivers professional-quality performance.
Pros:
- High nitrogen
- Fast greening
- Slow release
- Iron enriched
- Versatile use
- Long lasting
- Trusted brand
Cons:
- High nitrogen
- Not organic
- Requires watering
2. Milorganite 6-4-0 – Best organic fertilizer for St Augustine
Milorganite 6-4-0 offers a unique, heat-dried, slow-release organic fertilizer derived from recycled nutrients that provides consistent greening without burning. This non-burning, organic nitrogen source feeds St. Augustine grass gradually over 8-10 weeks, promoting steady, moderate growth that eliminates frequent mowing. The iron content delivers deep, rich greening without excessive top growth, resulting in a healthy, resilient lawn.
- You don’t have to worry about streaks, stripes, or accidentally burning your lawn when you use Milorganite fertilizer!
- Milorganite contains virtually no salts, so it won’t burn your lawn, trees, shrubs, or plants, even in the hottest temperatures or driest conditions.
The organic matter improves soil structure and water retention over time, building a healthier root system that withstands drought and foot traffic. This fertilizer is safe for use around children and pets, making it ideal for family lawns where safety is a primary concern. The product’s slow-release characteristic ensures nutrients remain available for extended periods, reducing the risk of leaching into water systems.
Apply this product to dry grass and water lightly to begin the nutrient release process. The 36-pound bag covers an impressive 2,500 square feet, delivering exceptional value for organic lawn care. For environmentally conscious homeowners, Milorganite provides sustainable nutrition that builds soil health while greening the lawn.
Pros:
- Organic nitrogen
- Slow release
- Iron enriched
- No burn risk
- Safe for pets
- Soil improving
- Cost effective
Cons:
- Faint odor
- Low potassium
- Slow greening
3. Andersons 16-0-8 SumoMaxx – Best professional-grade fertilizer for St Augustine
Andersons 16-0-8 SumoMaxx provides a balanced professional-grade formulation with a 2:1 nitrogen-to-potassium ratio ideal for St. Augustine grass. This formulation includes DMPP nitrification inhibitor technology that keeps nitrogen in the root zone longer, promoting steady growth and rich color. The 25% slow-release nitrogen ensures extended feeding for up to 12 weeks, reducing application frequency while maintaining consistent grass growth.
- Formulated with the perfect 4:1:2 (24-6-12) ratio for high-performance results Includes iron and micronutrients for total nutrition. Super-fine particles provide even distribution, with twice the number of particles per square foot.
- Quick and slow release nitrogen allows for immediate nutrition and extended feeding for up to 6 weeks. Includes micronutrients and iron for total nutrition and an extra-deep greening.
The DMPP technology reduces nitrogen loss through leaching and volatilization, making this product particularly effective in sandy soils common in St. Augustine growing regions. The high potassium content supports root development and stress tolerance, helping St. Augustine withstand heat and drought. This professional-grade formulation delivers the same results used by golf course superintendents and sports field managers.
Apply this product using a broadcast spreader on dry grass, following the recommended settings for your specific spreader model. The 50-pound bag covers up to 12,500 square feet, making it a cost-effective choice for larger lawns. For homeowners seeking commercial-quality results, Andersons provides professional-grade performance at an accessible price.
Pros:
- Professional grade
- DMPP technology
- Extended release
- Large coverage
- Heat tolerance
- Cost effective
- Consistent results
Cons:
- Not organic
- Requires spreader
- Large package
4. Simple Lawn Solutions 15-0-1 Liquid Fertilizer – Best liquid fertilizer for St Augustine
Simple Lawn Solutions 15-0-1 Liquid Fertilizer provides an ultra-concentrated, fast-acting formula that delivers visible greening within 24-48 hours of application. The high nitrogen content promotes rapid blade growth and deep green color while the sea kelp extract enhances root development and stress tolerance. This liquid formulation covers up to 3,200 square feet per quart, making it highly efficient and cost-effective for St. Augustine maintenance.
- Complete NPK Lawn Food: 16-4-8 is the perfect blend of key macronutrients. This lawn liquid food turf fertilizer also contains Seaweed & Fish.
- Contains High Quality Feed Grade Ingredients: Nourish your lawn with pure liquid Nutrients in a ready to use sprayer
The liquid format ensures even distribution and immediate nutrient uptake through both roots and grass blades, eliminating the need for post-application watering. The formulation includes amino acids that help grass absorb nutrients more efficiently, maximizing the greening effect with minimal product waste. This product works exceptionally well for quick lawn preparation before events, providing a fast green-up that traditional granular products cannot match.
Apply using a hose-end sprayer or tank sprayer, following the dilution instructions carefully for optimal results. The product is suitable for all St. Augustine varieties and provides a quick solution for homeowners seeking immediate lawn improvement. For those who value convenience and speed, Simple Lawn Solutions delivers rapid results with minimal effort.
Pros:
- Rapid greening
- Liquid formula
- Sea kelp added
- Even coverage
- Versatile use
- Cost efficient
- Easy application
Cons:
- Frequent use
- No slow release
- Requires sprayer
5. Lesco 30-0-10 St. Augustine Fertilizer – Best high-nitrogen professional formulation
Lesco 30-0-10 St. Augustine Fertilizer delivers a high-nitrogen formulation designed specifically for the nutritional needs of St. Augustine grass. The 3:1 ratio provides ample nitrogen for growth while the elevated potassium supports root strength and stress tolerance. This product includes 50% slow-release nitrogen for extended feeding and consistent grass color.
- Includes 6% Iron for Excellent Greening.
- 12,000 Sq.ft Coverage
The formulation is particularly effective for St. Augustine lawns emerging from winter dormancy, providing the nutrients needed for vigorous spring growth. The high potassium content helps grass withstand the transition from cool to warm weather and resist fungal diseases common in humid climates. This professional-grade product is widely used by landscape contractors and turf managers.
Apply using a broadcast spreader on dry grass, following the recommended settings for your specific spreader model. The 50-pound bag covers up to 12,500 square feet, making it a cost-effective choice for larger lawns. For homeowners seeking professional-grade St. Augustine results, Lesco delivers exceptional performance.
Pros:
- Professional grade
- High nitrogen
- Slow release
- Large coverage
- Disease resistance
- Cost effective
- Consistent results
Cons:
- Not organic
- Requires spreader
- Large package
6. GreenView St. Augustine Lawn Food 24-0-6 – Best long-lasting fertilizer for St Augustine
GreenView St. Augustine Lawn Food 24-0-6 features a 100% slow-release nitrogen formulation that provides consistent feeding for up to 12 weeks. This high-nitrogen blend promotes vigorous St. Augustine growth and deep green color while the elevated potassium supports root strength and drought resistance. The product includes 2% iron for additional greening, ensuring lawns maintain rich color between applications.
- GreenSmart Enhanced Efficiency Fertilizer provides continuous feeding for up to 8 weeks
- Restores nutrients to the soil and helps lawn retain water to protect against heat and drought
The extended feeding schedule reduces the number of applications needed per season, making it cost-effective and convenient for homeowners. This product is suitable for all St. Augustine varieties and can be applied during spring, summer, or fall depending on the lawn’s needs. The formula’s balanced nutrition helps St. Augustine recover from stress and maintain health throughout challenging weather conditions.
Apply using a broadcast spreader on dry grass and water thoroughly after application for optimal absorption. The 42-pound bag covers up to 10,000 square feet, offering excellent coverage for larger lawns. For homeowners seeking low-maintenance lawn care, GreenView delivers long-lasting nutrition with minimal effort.
Pros:
- Long lasting
- High nitrogen
- Iron enriched
- Versatile use
- Large coverage
- Cost effective
- All season use
Cons:
- Not organic
- Requires spreader
- Heavy bag
7. Simple Lawn Solutions Total Lawn Food 16-4-8 – Best comprehensive liquid fertilizer for St Augustine
Simple Lawn Solutions Total Lawn Food 16-4-8 delivers a comprehensive liquid fertilizer that provides balanced nutrition for all St. Augustine varieties. This complete formulation includes both macro and micronutrients essential for healthy lawn growth, development, and stress resistance. The liquid format ensures even application and rapid nutrient uptake for visible results within days.
- Complete NPK Lawn Food: 16-4-8 is the perfect blend of key macronutrients. This lawn liquid food turf fertilizer also contains Seaweed & Fish.
- Contains High Quality Feed Grade Ingredients: Nourish your lawn with pure liquid Nutrients in a ready to use sprayer
The inclusion of sea kelp extract promotes strong root development and enhanced stress tolerance for St. Augustine lawns. This product is particularly effective for lawns recovering from drought, disease, or heavy foot traffic, providing the nutrients needed to rebuild vigor. The balanced N-P-K ratio supports consistent growth without the surge-and-fade pattern of high-nitrogen products.
Apply using a hose-end sprayer for uniform coverage across the entire lawn. The concentrated formula covers up to 3,200 square feet per quart, delivering exceptional value. For homeowners seeking a comprehensive liquid fertilizer, Simple Lawn Solutions provides complete lawn nutrition in one convenient package.
Pros:
- Complete formula
- Liquid format
- Sea kelp added
- Quick results
- Stress recovery
- Versatile use
- Easy application
Cons:
- Frequent use
- No slow release
- Requires sprayer
8. Jobe’s Organics St. Augustine Fertilizer 16-0-4 – Best organic-based fertilizer for St Augustine
Jobe’s Organics St. Augustine Fertilizer 16-0-4 features a high-nitrogen organic-based formulation that delivers deep greening while building soil health. This Biozome-enriched formula contains beneficial bacteria, fungi, and microbes that accelerate nutrient breakdown and improve root development. The extended-release nitrogen provides consistent feeding for up to 8 weeks, promoting even growth without the surge-and-fade cycles.
- Package contains 4 pounds organic vegetable and tomato fertilizer grains and is produced to avoid wasteful runoff, mess, hazards and smells
- Plant fertilizer is formulated with a 2-5-3 NPK to provide vegetables and tomatoes the nutrients they need to create high yield and vibrant foliage
The organic matter improves soil texture and water retention over time, creating a healthier, more resilient St. Augustine lawn. This product is safe for use around children and pets, making it ideal for family lawns where safety is important. The Biozome technology enhances nutrient uptake efficiency, ensuring grass receives maximum benefit from every application.
Apply using a broadcast spreader on dry grass and water lightly to activate the nutrients. The 20-pound bag covers up to 5,000 square feet, making it suitable for medium-sized lawns. For homeowners seeking organic benefits with professional performance, Jobe’s delivers reliable results.
Pros:
- Biozome included
- Slow release
- Safe for pets
- Soil improving
- Consistent growth
- Organic based
- Versatile use
Cons:
- No potassium
- Higher cost
- Needs watering
9. Ringer Lawn Restore II 10-0-6 – Best natural fertilizer for St Augustine
Ringer Lawn Restore II 10-0-6 offers a natural, slow-release fertilizer that promotes healthy St. Augustine growth while improving soil conditions. This product contains poultry manure, feather meal, and other natural ingredients that provide consistent nutrition over several months. The 10-0-6 ratio emphasizes nitrogen for color and potassium for root health, creating a balanced approach to lawn nutrition.
- REVIVE GRASS ROOTS: Safer Brand Lawn Restore revitalizes lawn to a thick turf by strengthening root systems
- WORKS FAST: Lawns start to green up within 3 to 5 days of application
The natural ingredients feed beneficial soil organisms, building a healthy ecosystem that supports strong grass root development. This product is particularly effective for St. Augustine lawns with compacted or poor soils, as the organic matter improves soil structure and drainage. The 10-0-6 formulation supports deep root growth, reducing the need for frequent watering and improving drought tolerance.
Apply using a broadcast spreader on dry grass and water thoroughly to activate the nutrients. The 25-pound bag covers up to 5,000 square feet, providing excellent organic lawn care coverage. For gardeners committed to natural lawn maintenance, Ringer Lawn Restore II delivers pure, effective nutrition without synthetic chemicals.
Pros:
- Natural formula
- Slow release
- Soil improving
- Safe for pets
- Drought tolerance
- Deep roots
- Versatile use
Cons:
- Slower results
- No phosphorus
- Higher cost
10. Dr. Earth St. Augustine Fertilizer 9-0-2 – Best sustainable fertilizer for St Augustine
Dr. Earth St. Augustine Fertilizer 9-0-2 features a premium organic formulation that provides sustainable lawn nutrition without synthetic chemicals. This blend contains feather meal, fish meal, and kelp meal, delivering a diverse nutrient profile that promotes consistent growth and rich color. The organic ingredients feed soil organisms, building a healthy, resilient St. Augustine ecosystem over time.
- For more nutritious and tasty vegetables
- Optimum levels of primary plant nutrients
The 9-0-2 ratio emphasizes nitrogen for growth while the kelp meal provides essential micronutrients and growth stimulants for enhanced root development. This product is safe for use around children and pets, making it ideal for family lawns where safety is important. The slow-release organic nitrogen provides consistent feeding for up to 8 weeks, promoting steady growth without excessive mowing.
Apply using a broadcast spreader on dry grass and water lightly to activate the nutrients for optimal absorption. The 12-pound bag covers up to 2,500 square feet, making it suitable for smaller to medium-sized lawns. For environmentally conscious homeowners, Dr. Earth delivers sustainable nutrition that builds soil health while greening the lawn.
Pros:
- Organic certified
- Slow release
- Safe for pets
- Soil building
- Diverse nutrients
- Sustainable
- Versatile use
Cons:
- Higher cost
- No phosphorus
- Slower results
Frequently Asked Questions About Fertilizer For St Augustine
1. What is the best fertilizer for St. Augustine grass?
Scotts Turf Builder, Andersons SumoMaxx, and Milorganite rank among the best fertilizers for St. Augustine grass. The optimal choice depends on your soil conditions, application preference, and whether you prefer organic or synthetic formulations.
2. When should I fertilize St. Augustine grass?
Fertilize St. Augustine in spring when it reaches 50% green-up, again in early summer for peak growth, and in late summer to maintain vigor. Avoid fertilizing in fall as this can promote growth that may be damaged by winter cold.
3. What N-P-K ratio is best for St. Augustine grass?
St. Augustine grass thrives with higher nitrogen ratios such as 32-0-4, 16-4-8, or 15-5-10, which promote growth and color. Balanced formulations with slow-release nitrogen provide the best results for this warm-season grass.
4. How often should I fertilize St. Augustine grass?
Apply fertilizer to St. Augustine every 6-8 weeks during the active growing season, or according to the product’s specific instructions. Slow-release fertilizers require less frequent application than quick-release formulations.
5. Can I over-fertilize St. Augustine grass?
Yes, over-fertilizing can cause excessive thatch buildup, nutrient burn, and increased disease susceptibility. Always follow label instructions and conduct soil tests to determine exact nutrient needs.
6. Is organic or synthetic fertilizer better for St. Augustine?
Organic fertilizers improve soil health over time but work more slowly, while synthetic fertilizers provide quick results. The best choice depends on your goals for lawn appearance and long-term soil health.
7. Should I water St. Augustine grass after fertilizing?
Most granular fertilizers require thorough watering after application to activate nutrients and move them into the soil. Watering also helps prevent fertilizer burn by washing granules off grass blades.
Conclusion
In conclusion, selecting the best fertilizer for St Augustine transforms your lawn into a lush, heat-tolerant carpet that enhances your home’s curb appeal. Scotts Turf Builder Southern Lawn Food earned our top recommendation for its high-nitrogen formulation, slow-release technology, and iron enrichment that delivers rapid greening with sustained results for St. Augustine lawns. Andersons SumoMaxx emerged as the runner-up for its professional-grade performance, DMPP technology that reduces nitrogen loss, and extended feeding that provides consistent nutrition for up to 12 weeks. Both products excel in their categories, addressing different priorities including speed of greening, nutrient efficiency, and professional performance. The remaining eight products provide specialized advantages for specific needs, from organic Milorganite to comprehensive liquid options.
Each fertilizer reviewed above offers unique benefits tailored to specific St. Augustine conditions and homeowner preferences. Consider your soil type, application method preference, and desired results when making your selection. The right fertilizer creates a beautiful, healthy St. Augustine lawn that enhances your outdoor living experience.
Investing in quality fertilizer for your St. Augustine lawn enhances grass health, improves curb appeal, and creates lasting environmental benefits. Regular feeding, proper application, and seasonal care ensure your lawn remains vibrant throughout the hot summer months. The modest investment in quality fertilizer returns significant dividends in beauty, comfort, and property value.
Ready to transform your St. Augustine lawn with the best fertilizer for St Augustine? Choose from our recommended options above and experience the difference in lawn quality and appearance. Browse our selection today and plant the foundation for a lush, green yard. Start your fertilizing routine now and enjoy a beautiful lawn that impresses neighbors and guests.