Does your St. Augustine lawn look patchy, with stubborn weeds popping up everywhere? You want that lush, green carpet, but fighting weeds while feeding the grass feels like a constant battle. Choosing the right “Weed and Feed” product for this specific type of grass adds another layer of confusion. Many homeowners grab the first bag they see, only to find it harms their sensitive St. Augustine blades or simply doesn’t stop the crabgrass.
Getting this balance wrong means wasting money and ending up with a lawn that looks worse, not better. You need a product that knocks out the weeds without stressing your warm-season grass. This guide cuts through the confusing labels and complicated instructions.
By the end of this post, you will know exactly what ingredients to look for, which products work best for St. Augustine, and how to apply them correctly for maximum results. Let’s dive into creating the healthiest, weed-free St. Augustine lawn possible.
Top Weed And Feed Fertilizer For St Augustine Grass Recommendations
- FOR SOUTHERN LAWNS: 3-In-1 Weed and Feed is specially formulated to target types of weeds found in Southern lawns, like Bermudagrass, St. Augustinegrass and more
- PREVENTS NEW WEEDS UP TO 6 MONTHS: One application prevents listed weeds for up to 6 months; Apply when temperatures are between 50 and 90 degrees and weeds are actively growing
- KILLS SOUTHERN WEEDS: Kills Dandelion, Dollarweed, Clover, and other listed broadleaf weeds
- FEEDS & GREENS: Fertilizer feeds and greens your lawn for up to 3 months to promote thicker, healthier turf; Apply granules with a broadcast or drop spreader for smooth, even coverage across established lawns
- GET MORE FROM THE BLUE BOTTLE: From simple spot treatments to season-long protection, BioAdvanced science-based solutions make it simple to control unsightly weeds, feed your lawn, and protect against damaging diseases without harming the lawn, when used as directed
- Easy to spread granules and easy to handle
- 2 applications in the spring and fall
- Can be used on all types of St. Augustine grasses
- This pre-emergent and post-emergent herbicide controls weeds and provides a 15-0-4 fertilizer mix.
- The fertilizer is designed for Centipede, Zoysia and St. Augustine lawns and grass types.
- Do not use this product on Bermuda Grasses or any other type of Northern grass.
- Apply the product in early spring for improved lawn health and weed defense throughout the season.
- Application varies by footage. See label for application instruction.
- Lesco Professional, 50 LB, 13,00 SQFT, 17-0-17 St Augustine Turf Fertilizer
- 30% Poly Coated Sulfur Coated Urea, Specially For St. Augustine Grass
- Should Be Applied When Turf Is Wet, Allow To Dry & Total Results In 2 Weeks, Safe For Floratam Variety, Slow Release Providing Up To 8 Weeks Of Feeding
- Its very easy and elegant to use
- FOR SOUTHERN LAWNS: 3-In-1 Weed and Feed is specially formulated for use on Southern lawns, including Bermudagrass (except Ormond variety) and St. Augustinegrass, to control listed weeds; Refer to the label for a complete list of weeds and turf types
- PREVENTS NEW WEEDS UP TO 6 MONTHS: One application prevents listed weeds for up to 6 months; Apply when temperatures are between 50 and 90 degrees and weeds are small and actively growing
- KILLS SOUTHERN WEEDS: Kills Dandelion, Dollarweed, Clover, and other listed broadleaf weeds
- FEEDS & GREENS: Fertilizer feeds and greens your lawn to promote thicker, healthier turf; Apply granules with a broadcast or drop spreader for smooth, even coverage across established lawns
- GET MORE FROM THE BLUE BOTTLE: From simple spot treatments to season-long protection, BioAdvanced science-based solutions make it simple to control unsightly weeds, feed your lawn, and protect against damaging diseases without harming the lawn, when used as directed
- DUAL-ACTION FORMULA: Spectracide Weed & Feed 20-0-0 kills weeds while feeding your lawn.
- KILLS MAJOR BROADLEAF WEEDS: Kills dandelion, chickweed, knotweed, plantain, clover, mallow, purslane and many other broadleaf weeds.
- FEEDS LAWN: Formulated with 20% nitrogen to feed your lawn.
- COVERAGE: One 32-oz bottle treats up to 7,500 square feet.
- CONVENIENT THREE PACK: Three pack features one nozzle and three bottles of product.
- DUAL-ACTION FORMULA: Kills major broadleaf weeds while feeding your lawn.
- FEEDS LAWN: Fertilizes with 20 percent nitrogen formulation.
- KILLS WEEDS: Controls dandelion, chickweed, knotweed, plantain, clover, mallow, purslane and many broadleaf weeds as listed.
- QUICKFLIP SPRAYER: Just connect to your hose and spray – just grip, flip and go.
- COVERAGE: 32 ounces treats up to 7,500 square feet of lawn.
- COVERAGE: One 3.75 lb. shaker jug of Scotts EZ Patch Lawn Repair for St. Augustine Lawns covers up to 85 sq. ft. of lawn (this product does not contain grass seed for lawns)
- GRASS FERTILIZER: Lawn fertilizer with controlled release technology feeds to promote the growth and establishment of St. Augustinegrass, including sod and plugs
- FOR ST. AUGUSTINEGRASS REPAIR: EZ Patch Lawn Repair is a grass patch repair for lawns that helps St. Augustinegrass repair 60% faster (results 15 days after application vs untreated control; results may vary)
- READY-TO-USE MULCH: A lawn food product with mulch that absorbs up to 6 times its weight in water and expands to provide better coverage
- HOW TO APPLY: Apply this mulch and fertilizer grass repair mix by removing dead grass and loosening hard soil, applying an even layer of product, and gently watering until mix is saturated
Your Guide to Choosing the Best Weed and Feed for St. Augustine Grass
St. Augustine grass is a beautiful, thick lawn, but it needs the right care. Weed and feed products help your grass grow strong while stopping pesky weeds. Choosing the right one is important for a healthy, green yard. This guide helps you pick the best product for your St. Augustine lawn.
Key Features to Look For
When you shop for weed and feed, look for specific things on the bag. These features make a big difference in how well the product works.
- Weed Control Type: Some products kill existing weeds (post-emergent). Others stop new weeds from sprouting (pre-emergent). For St. Augustine grass, you often need a product that is safe for established lawns but stops summer weeds like crabgrass.
- Fertilizer Ratio (N-P-K): This shows the amount of Nitrogen (N), Phosphorus (P), and Potassium (K). Nitrogen makes the grass green and helps it grow. Look for a higher first number (N) for good growth.
- Slow-Release vs. Quick-Release: Slow-release nitrogen feeds your lawn over many weeks. This prevents sudden, fast growth that can stress the grass. Quick-release works fast but needs more frequent applications.
- Safety for St. Augustine: St. Augustine grass is sensitive. Ensure the bag clearly states it is safe for St. Augustine. Some herbicides can damage this grass type easily.
Important Materials in Weed and Feed
The ingredients determine if the product feeds your grass well and kills the right weeds.
Active Ingredients for Weed Killing
The herbicide part of the mix must target common lawn weeds without harming your St. Augustine turf. Common active ingredients that are generally safe for St. Augustine include 2,4-D, Dicamba, and MCPP. Always check the label to confirm safety. Some products use different chemicals that might hurt your grass.
Nutrient Sources
For feeding, look at the nitrogen source. Organic sources like Milorganite offer a slow, steady feed. Synthetic sources offer quicker results. Good weed and feed products use a mix or focus on slow-release nitrogen to support steady St. Augustine growth throughout the season.
Factors That Improve or Reduce Quality
The quality of a weed and feed product depends on how well it balances weed killing and grass feeding.
Quality Boosters
Products that include micronutrients like Iron (Fe) improve the deep green color of St. Augustine grass. Using a slow-release formula usually provides better, longer-lasting results. When the product is applied correctly, the quality improves.
Quality Reducers
Using a weed killer that is too strong for St. Augustine grass reduces quality immediately by burning or damaging the turf. Also, applying the product when temperatures are too high (over 85°F) can cause the grass to suffer, even if the product is usually safe.
User Experience and Use Cases
How easy the product is to use affects your overall experience.
Application Ease
Granular (pellet) weed and feed products are the most common. They require a spreader. Make sure the product flows smoothly through your spreader without clogging. Liquid concentrates need mixing with water and spraying, which some users find messier but offer more precise application.
When to Apply
The best time to use a pre-emergent weed and feed is in early spring before weeds like crabgrass germinate. Post-emergent applications happen when you see active weeds growing. St. Augustine grass grows fastest in warm weather, so feeding during its active growing seasons (late spring through summer) works best.
10 Frequently Asked Questions (FAQ) About Weed and Feed for St. Augustine Grass
Q: Can I use any weed and feed on my St. Augustine lawn?
A: No. St. Augustine grass is sensitive. You must choose a product that specifically says it is safe for St. Augustine turf. Other herbicides can cause serious damage.
Q: When is the best time to apply weed and feed to St. Augustine grass?
A: Apply pre-emergent weed and feed in early spring when soil temperatures are right, usually before spring rains. Always check the bag instructions for the best timing for your region.
Q: Will this product kill clover and dandelions in my St. Augustine lawn?
A: Most standard weed and feed products kill broadleaf weeds like clover and dandelions. Check the label to confirm the specific weeds it controls.
Q: How soon after applying can my dog walk on the lawn?
A: After spreading granular fertilizer, you should water it in lightly. Wait until the grass is completely dry before letting pets or children walk on the treated area. This usually takes a few hours.
Q: What does the N-P-K ratio mean on the bag?
A: N-P-K stands for Nitrogen, Phosphorus, and Potassium. Nitrogen (the first number) is most important for green growth.
Q: Should I water my lawn before or after applying weed and feed?
A: Generally, you should water lightly *after* applying granular products to help the nutrients move into the soil. Never apply when rain is expected soon, as heavy rain washes the product away.
Q: My St. Augustine grass looks yellow. Will weed and feed fix it?
A: Nitrogen in the weed and feed helps green up yellow grass. However, severe yellowing might mean a nutrient deficiency (like iron) or a disease. The fertilizer will help with nutrient-related yellowing.
Q: How often should I use weed and feed products?
A: This depends on the product. Pre-emergent weed and feed is often applied twice a year (early spring and late summer). Follow the recommended reapplication intervals listed on the packaging.
Q: What is the difference between pre-emergent and post-emergent weed control?
A: Pre-emergent stops seeds from sprouting. Post-emergent kills weeds that are already growing above the soil line.
Q: Can I use a weed and feed product if I just laid down new St. Augustine sod?
A: No. Wait several weeks after laying new sod before applying any weed and feed. New grass roots need time to establish without herbicide exposure.