10 Best Fertilizers for Saint Augustine Grass in 2026

{{post_2026}}
Thoms
Written By Thomas James

BestStrollersFinder is a participant in the Amazon Services LLC Associates Program. Some links on this site are affiliate links, which means we may earn a small commission if you make a purchase at no extra cost to you. We only recommend products we trust, and all content is honest and unbiased.

Why is my lawn yellowing while the neighbor’s grass looks like a thick, dark green carpet? Achieving that lush appearance requires the right chemistry, specifically calibrated for the unique needs of your turf.

Picking the Best Fertilizers for Saint Augustine Grass is like choosing the right fuel for a high performance engine. You need the correct nutrient ratios to encourage healthy growth without burning the delicate blades. Keep reading to see which options match your maintenance goals.

Key Takeaways

  • Prioritize formulas with high nitrogen content to support the vigorous leaf production that this grass type requires.
  • Choose phosphorus free options if your local regulations or soil tests indicate that additional phosphorus is unnecessary for your lawn.
  • Consider a mix of quick release and slow release nitrogen to provide an immediate color boost while maintaining growth over several weeks.
  • Verify whether your product includes pre-emergent or post-emergent herbicides, as applying weed killer at the wrong time can damage newly established runners.
  • Match your application method to your equipment, as granular products require a broadcast spreader while liquid concentrates need a hose end sprayer.

Our Top Best Fertilizers For Saint Augustine Grass Picks

Top Overall Choice Sunniland St. Augustine Weed and Feed Combines fertilizer and herbicide Formulated for St. Augustine Covers 5000 square feet View on Amazon Read Review
Fast Acting Nutrition St. Augustine Liquid Lawn Food Rapid nutrient delivery Promotes rich color Encourages new runners View on Amazon Read Review
Best Slow Release Sunniland 20-0-6 Granular Lawn Fertilizer Steady nitrogen release Phosphorus free formula Ideal for turf density View on Amazon Read Review
Professional Grade Nutrient SeedRanch St. Augustine 24-2-11 Fertilizer High nutrient concentration Supports large lawns Optimized for St. Augustine View on Amazon Read Review
Heavy Duty Protection LESCO St. Augustine Weed and Feed Effective weed suppression Contains Penoxsulam Robust feeding program View on Amazon Read Review
Most Versatile Liquid Simple Lawn Solutions Balanced Fertilizer Balanced nutrient ratio Easy hose-end application Works on any grass View on Amazon Read Review
Reliable Household Staple Scotts Turf Builder Lawn Food Consistent growth results Strengthens root systems Widely available View on Amazon Read Review
Summer Pest Defense Scotts SummerGuard Insect Control Dual-action insect control Seasonal lawn feeding Protects against damage View on Amazon Read Review
Best Spot Repair Scotts EZ Patch Repair Mix All-in-one patch kit Includes soil mulch Promotes quick regrowth View on Amazon Read Review
Best Iron Supplement Fertilome Slow-Release Iron Fertilizer High iron content Slow-release nitrogen Excellent for color View on Amazon Read Review

More Details on Our Top Picks

  1. Sunniland St. Augustine Weed and Feed

    Top Overall Choice

    View on Amazon

    If you want a dual-action solution that tackles both nutrition and unwanted weeds, this is your best bet. It functions like a sturdy workhorse, delivering consistent nutrients while keeping encroaching plants at bay.

    You will appreciate how it specifically targets the needs of St. Augustine grass to ensure the turf remains dense and healthy. Just be mindful that because it includes a weed killer, you should avoid applying it near ornamental flower beds where the herbicide could cause unintended damage.

    • Brand Name:Sunniland
    • Product Type:Granular Weed and Feed
    • Coverage Area:5000 square feet
    • Additional Feature:Targeted weed control
    • Additional Feature:Granular application
    • Additional Feature:St. Augustine specific formulation
  2. St. Augustine Liquid Lawn Food

    Fast Acting Nutrition

    View on Amazon

    Sometimes your grass needs a quick boost rather than a slow, long-term release. This liquid formula is excellent for those looking to encourage thicker growth and a vibrant, deep green color in a short window of time.

    It is particularly helpful for jump-starting root development when the growing season is in full swing. Keep in mind that liquids generally require more frequent applications than granular options because they wash through the soil profile more quickly.

    • Product Type:Liquid Fertilizer
    • Total Weight:1 gallon
    • Additional Feature:Supports root growth
    • Additional Feature:Easy mix and feed
    • Additional Feature:High nitrogen formula
  3. Sunniland 20-0-6 Granular Lawn Fertilizer

    Best Slow Release

    View on Amazon

    Feeding your lawn shouldn't be a constant chore, and this slow release nitrogen formula helps you step back and let the grass do the work. By providing nutrients gradually, it prevents the flush of growth that leads to excessive mowing.

    The phosphorus free composition makes it a smart pick for environmental safety, especially if you live near waterways. It serves as a reliable foundation for sustained, steady growth throughout the season.

    • Brand Name:Sunniland
    • Formula Ratio:20-0-6
    • Product Type:Granular Fertilizer
    • Total Weight:40 pounds
    • Coverage Area:10000 square feet
    • Additional Feature:Slow release nitrogen
    • Additional Feature:Turf health maintenance
    • Additional Feature:Two bag pack
  4. SeedRanch St. Augustine 24-2-11 Fertilizer

    Professional Grade Nutrient

    View on Amazon

    If you manage a large property, you likely want a high-capacity bag that doesn't run out halfway through the job. This nutrient dense blend packs a punch, providing the specific ratios that St. Augustine grass craves to thrive.

    The high nitrogen content helps maintain that lush, deep green carpet look that everyone wants. Just make sure you have a quality broadcast spreader to distribute the 50 pounds of material evenly across your yard.

    • Brand Name:SeedRanch
    • Formula Ratio:24-2-11
    • Product Type:Granular Fertilizer
    • Total Weight:50 pounds
    • Additional Feature:Professional grade blend
    • Additional Feature:Supports dense growth
    • Additional Feature:Large format bag
  5. LESCO St. Augustine Weed and Feed

    Heavy Duty Protection

    View on Amazon

    This option is essentially the heavy artillery of lawn care. By incorporating Penoxsulam, it manages to suppress tough weeds that often plague St. Augustine lawns while simultaneously feeding the soil.

    It is a great choice for homeowners who are tired of fighting a losing battle against stubborn invaders. Because this is a potent chemical product, you must read the application rates carefully to avoid stressing the grass.

    • Brand Name:LESCO
    • Product Type:Weed and Feed
    • Total Weight:50 pounds
    • Additional Feature:Targeted herbicide action
    • Additional Feature:Professional grade quality
    • Additional Feature:Granular delivery
  6. Simple Lawn Solutions Balanced Fertilizer

    Most Versatile Liquid

    View on Amazon

    You don't always need a massive bag of chemicals to get results, and this balanced liquid is proof. Its 16-4-8 ratio is like a multivitamin for your lawn, providing a little bit of everything needed to keep grass happy and resilient.

    Since it is a concentrated spray, it is remarkably easy to use with a standard hose-end sprayer. It is perfect if you want to perform spot treatments on patches that are looking a little yellow.

    • Brand Name:Simple Lawn Solutions
    • Formula Ratio:16-4-8
    • Product Type:Liquid Fertilizer
    • Total Weight:32 ounces
    • Additional Feature:Concentrated formula
    • Additional Feature:Simple to apply
    • Additional Feature:Spring and summer use
  7. Scotts Turf Builder Lawn Food

    Reliable Household Staple

    View on Amazon

    Sometimes you just need a product that works consistently without any mystery. This is the classic standard for a reason, as it delivers a reliable feed that helps build strong, deep roots.

    It is designed to be user friendly for those who are not lawn experts but still want a green yard. While it works on all grass types, it performs quite well when applied to a healthy, established St. Augustine lawn.

    • Brand Name:Scotts
    • Product Type:Granular Fertilizer
    • Total Weight:12.5 pounds
    • Coverage Area:5000 square feet
    • Additional Feature:Turf builder technology
    • Additional Feature:All-season utility
    • Additional Feature:Easy application
  8. Scotts SummerGuard Insect Control

    Summer Pest Defense

    View on Amazon

    Summer heat often brings out the bugs, and this product serves as both a fertilizer and defender. It is a clever way to kill off lawn-damaging insects while keeping your grass fed during the hottest months.

    You will find it quite useful if your lawn has a history of pest issues during the late summer. Just be aware that it is a specialized tool, so use it primarily when you actually see signs of insect activity.

    • Brand Name:Scotts
    • Product Type:Fertilizer and Insecticide
    • Total Weight:13.35 pounds
    • Coverage Area:5000 square feet
    • Additional Feature:Kills lawn pests
    • Additional Feature:Summer stress support
    • Additional Feature:Granular treatment
  9. Scotts EZ Patch Repair Mix

    Best Spot Repair

    View on Amazon

    If your lawn has a few unsightly bald spots, you don't need to treat the whole yard. This patch mix acts like a bandage, combining mulch, seed, and fertilizer into one simple, effective solution.

    It is ideal for high-traffic areas or spots where the St. Augustine grass has thinned out. The mulch component helps hold moisture in the soil, which is vital for new growth to take hold.

    • Brand Name:Scotts
    • Product Type:Repair Mix
    • Total Weight:3.75 pounds
    • Coverage Area:170 square feet
    • Additional Feature:Moisture-holding mulch
    • Additional Feature:Fertilizer included
    • Additional Feature:Two pack convenience
  10. Fertilome Slow-Release Iron Fertilizer

    Best Iron Supplement

    View on Amazon

    When your grass looks pale, it is often crying out for a bit of iron. This formula is a specialist treatment that focuses on deep color and slow-release nutrition, making it a favorite for those who want that dark, rich aesthetic.

    It is particularly effective for warm-season grasses that have trouble absorbing nutrients in alkaline soil. It is more about enhancing the color and vigor than forcing massive, rapid growth.

    • Brand Name:Fertilome
    • Formula Ratio:15-0-15
    • Product Type:Granular Fertilizer
    • Total Weight:16 pounds
    • Additional Feature:High iron boost
    • Additional Feature:Warm-season formula
    • Additional Feature:Consistent delivery

Factors to Consider When Choosing Best Fertilizers For Saint Augustine Grass

Nitrogen Content Ratio

Saint Augustine grass is a heavy feeder that craves nitrogen to maintain its deep green color and thick growth. Look for a fertilizer with a high first number in the NPK ratio, ideally something like 21-0-0 or a balanced blend with a slow release component. This ensures the grass gets a steady diet rather than a sudden, unsustainable growth spurt.

Slow Release Formula

You want a fertilizer that uses coated granules or organic matter to release nutrients over time. This prevents the dreaded nitrogen burn that can turn your lawn brown overnight. A slow release product typically feeds your turf for 6 to 8 weeks, which saves you from constant reapplications.

Iron Supplementation

If your lawn looks yellow even after you fertilize, it might be starving for iron rather than nitrogen. Adding chelated iron to your routine helps the grass produce chlorophyll, which gives it that vibrant green appearance. Many Saint Augustine formulas include iron specifically to combat the high pH levels common in many soils.

Soil pH Compatibility

Saint Augustine grass prefers a slightly acidic soil, usually between 6.0 and 7.5. If your soil is too alkaline, the grass cannot absorb nutrients effectively. Choose a fertilizer that contains sulfur or other acidifying agents to help keep the pH in that sweet spot for maximum nutrient uptake.

Application Timing

Timing is everything when it comes to healthy turf. Start your first application in the early spring once the grass has fully greened up and is actively growing. Avoid fertilizing during the dead of winter, as the grass is dormant and won't be able to use the nutrients, leading to wasteful runoff.

Frequently Asked Questions

How often should I fertilize my Saint Augustine lawn?

Aim for four to six applications per year during the active growing season. Space them out by about six to eight weeks to ensure consistent growth.

Can I use a weed and feed product?

You can, but you must be careful because many herbicides in these products can damage Saint Augustine. Always check the label to ensure it is safe for your specific grass type before you spread it.

Should I water after applying fertilizer?

Yes, you should always lightly water your lawn after application. This helps wash the granules off the grass blades and into the soil where the roots can actually reach them.

Will fertilizer fix my brown patches?

Fertilizer helps with nutrient deficiencies, but brown patches are often caused by fungus or pests. Check for signs of disease before applying more fertilizer, as extra nitrogen can actually make some fungal problems grow faster.

Is organic fertilizer better than synthetic?

Organic options improve your soil health over time, while synthetic fertilizers provide a faster, more concentrated nutrient boost. Many homeowners find that a hybrid approach using both types offers the best balance of speed and long term soil quality.

Leave a Comment