10 Best Late Summer Fertilizers to Keep Your Lawn Green Through Fall

I’ve found that late summer fertilizers like Scotts Turf Builder SummerGuard and WinterGuard deliver exceptional results for maintaining lawn health through fall shifts. These formulations strengthen root systems, enhance drought resistance, and work effectively on various grass types including Bermuda, St. Augustine, and Zoysia. The key lies in choosing fertilizers with lower nitrogen content and higher potassium ratios to prevent excessive growth while building resilience. Below, you’ll discover specific application strategies and timing recommendations.

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Notable Insights

• Scotts Turf Builder SummerGuard combines fertilizer with insect control, covering 5,000 sq. ft. while strengthening grass against heat and drought stress.
• Choose fertilizers with lower nitrogen and higher potassium ratios to promote root growth without excessive top growth during late summer.
• Apply fertilizers when nighttime temperatures drop into the 60s and grass is actively growing for optimal nutrient absorption.
• Scotts WinterGuard Fall Fertilizer builds strong root systems and repairs summer damage from heat and foot traffic on all grass types.
• Iron-supplemented fertilizers like Scotts Green Max provide visible greening within three days and work effectively in spring, summer, or fall.

Scotts Turf Builder SummerGuard Lawn Food with Insect Control (5,000 sq. ft.)

When dealing with both undernourished grass and persistent insect problems, Scotts Turf Builder SummerGuard Lawn Food with Insect Control offers the perfect dual-action solution for busy homeowners. This thorough treatment covers 5,000 square feet with just 13.35 pounds of granules, making application efficient and straightforward. You’ll effectively eliminate troublesome pests like ants, chinch bugs, fleas, and ticks while simultaneously feeding your lawn essential nutrients. The fertilizer strengthens grass against late summer heat and drought stress, preparing it for fall’s cooler temperatures. Apply the granules to dry grass using recommended spreader settings, then water thoroughly for ideal results.

Best For: Homeowners dealing with both undernourished lawns and insect infestations who want a convenient dual-action treatment that feeds grass while eliminating pests like ants, chinch bugs, fleas, and ticks.

Pros:

• Combines fertilizer and insect control in one application, saving time and effort
• Covers large area efficiently with 5,000 sq. ft. coverage from just 13.35 lbs of granules
• Strengthens grass against summer heat and drought stress while eliminating multiple pest types

Cons:

• Requires waiting at least one week before applying other pest or weed control products
• Must be applied to dry lawn and watered afterward, requiring specific timing conditions
• Limited to summer application timing when insect activity is first observed

Scotts Turf Builder WinterGuard Fall Lawn Fertilizer (5,000 sq. ft.)

Homeowners seeking thorough lawn preparation for winter’s harsh conditions will find Scotts Turf Builder WinterGuard Fall Lawn Fertilizer an exceptional choice for late summer application. This 12.5-pound bag covers 5,000 square feet and works effectively on all grass types, making it versatile for various lawn conditions. You’ll appreciate how it builds strong, deep root systems that enhance your lawn’s ability to absorb water and nutrients throughout the challenging months ahead. The fertilizer delivers essential nutrients that repair damage from summer heat, drought, and foot traffic while strengthening roots to withstand winter’s severity. Applying this fall-specific formula guarantees your lawn receives ideal preparation for next year’s growing season.

Best For: Homeowners with any grass type who want to strengthen their lawn’s root system and prepare it to withstand winter conditions while repairing summer damage from heat, drought, and foot traffic.

Pros:

• Works on all grass types and covers 5,000 square feet with one 12.5-pound bag
• Builds strong, deep roots that improve the lawn’s ability to absorb water and nutrients
• Repairs damage from summer stressors while preparing the lawn for harsh winter conditions

Cons:

• Limited to fall application timing, reducing flexibility for year-round lawn care
• Coverage area of 5,000 square feet may require multiple bags for larger properties
• No mention of organic or environmentally-friendly ingredients for eco-conscious users

Scotts Green Max Lawn Food, Lawn Fertilizer Plus Iron Supplement (5,000 sq. ft.)

Scotts Green Max Lawn Food stands out as the ideal choice for gardeners seeking rapid lawn transformation, delivering visible greening results in just three days through its dual-action formula. This fertilizer combines essential nutrients with 5% iron supplement, creating a powerful combination that enhances your lawn’s color while strengthening root systems for long-term durability. You’ll appreciate the versatile application timing, as this product works effectively on any grass type during spring, summer, or fall seasons. One 16.67-pound bag covers 5,000 square feet, making it perfect for small to medium-sized lawns. While you’ll see immediate improvements, plan for potential reapplication to maintain sustained greening throughout the growing season.

Best For: Homeowners with small to medium-sized lawns who want quick greening results and don’t mind reapplying the product for sustained color throughout the growing season.

Pros:

• Fast-acting formula delivers visible greening results in just 3 days
• Dual-action fertilizer with 5% iron supplement strengthens roots while enhancing color
• Versatile application timing works on any grass type during spring, summer, or fall

Cons:

• Risk of lawn burn if applied incorrectly or during high temperatures
• Short-term greening effects require reapplication for lasting results
• Strong odor that may linger after application

Scotts Turf Builder Lawn Food Fertilizer (5,000 sq. ft.)

For gardeners seeking a versatile, all-purpose fertilizer that works across different grass varieties, Scotts Turf Builder Lawn Food offers extensive nutrition in a convenient 12.5-pound package. This formula strengthens your grass while building robust root systems that enhance water and nutrient absorption compared to unfed lawns. You’ll appreciate its flexibility since it works effectively on any grass type, whether you’re managing cool-season fescue or warm-season Bermuda. The application process couldn’t be simpler—you can spread it on wet or dry grass without worry. This single bag covers 5,000 square feet, providing thorough feeding that protects against future lawn problems throughout fall.

Best For: Homeowners with any grass type looking for a simple, all-purpose fertilizer that strengthens roots and improves nutrient absorption across 5,000 square feet.

Pros:

• Works effectively on all grass types, from cool-season fescue to warm-season Bermuda
• Can be applied to either wet or dry lawns for maximum flexibility
• Builds strong root systems that improve water and nutrient absorption compared to unfed lawns

Cons:

• Only covers 5,000 square feet, requiring multiple bags for larger properties
• No specific formulation for different grass types or seasonal needs
• Lacks targeted pest or weed control features found in combination products

Scotts Turf Builder Triple Action Weed Killer and Lawn Fertilizer (4,000 sq. ft.)

The triple-action formula in this thorough lawn treatment makes it an ideal choice for gardeners who want to tackle multiple lawn problems simultaneously during late summer application periods. You’ll effectively control existing broadleaf weeds like dandelions, clover, and dollarweed while preventing crabgrass germination for up to four months. This all-encompassing approach feeds your grass for thicker, greener growth across compatible varieties including Kentucky Bluegrass, Bermudagrass, and Tall Fescue. Apply the 11.31-pound bag on wet lawns using a Scotts spreader when weeds are actively growing, ensuring particles adhere properly to weed leaves for maximum effectiveness.

Best For: Homeowners looking for a comprehensive lawn care solution that simultaneously eliminates existing broadleaf weeds, prevents crabgrass for months, and fertilizes grass for healthier growth in one application.

Pros:

• Three-in-one formula saves time and effort by killing weeds, preventing crabgrass, and feeding grass in a single treatment
• Provides long-lasting crabgrass prevention for up to 4 months after application
• Compatible with multiple grass types including Kentucky Bluegrass, Bermudagrass, Tall Fescue, and others

Cons:

• Requires specific weather conditions (wet lawn) for proper application and effectiveness
• Safety restrictions prevent people and pets from accessing treated areas until dust settles
• Limited to 4,000 sq. ft. coverage requiring multiple bags for larger lawns

Scotts Turf Builder WinterGuard Fall Weed & Feed, 4,000 sq. ft

When you’re dealing with a lawn that’s battling both weeds and weak grass heading into winter, this dual-action fertilizer becomes an essential tool for thorough fall care. You’ll target over 50 common weeds, including stubborn clover, dandelion, and purslane, while simultaneously feeding your grass for stronger root development. Apply this product when temperatures stay between 60°F and 90°F on moist lawn surfaces, then avoid watering for 24 hours to guarantee proper adherence. Your spreader settings should be 3½ for broadcast models or 6 for drop spreaders across the 4,000 square foot coverage area. While you’ll see significant weed reduction and grass improvement, heavily infested lawns may require follow-up treatments for complete transformation.

Best For: Homeowners with moderately weedy lawns who want to simultaneously eliminate common weeds and strengthen grass roots for winter in a single fall application.

Pros:

• Dual-action formula targets over 50 weeds while feeding grass for stronger root development and winter preparation
• Covers large area efficiently with one 11.43 lb bag treating 4,000 square feet
• Users report significant lawn transformation with healthier, lusher grass and noticeable weed reduction when applied correctly

Cons:

• Not effective against all weed types like Poa annua and may require multiple applications for complete eradication
• Restricted grass compatibility as it cannot be used on St. Augustinegrass, Dichondra, Lippia, or Bentgrass
• Heavily infested lawns may need additional treatments beyond this product alone to achieve desired results

Scotts Turf Builder Weed & Feed3 Lawn Fertilizer (5,000 sq. ft.)

Combining two essential lawn care tasks into one efficient application, Scotts Turf Builder Weed & Feed3 delivers targeted nutrition and extensive weed control for homeowners managing medium-sized properties up to 5,000 square feet. You’ll appreciate its WeedGrip Technology, which eliminates over 50 common weeds including dandelions, clover, and plantain while simultaneously feeding your grass. For ideal results, apply when temperatures range between 60°F and 90°F, ensuring your lawn is wet beforehand for proper adherence. This versatile product works safely on most grass types, including Bermudagrass, Fescue, and Zoysiagrass, though you should avoid using it on St. Augustinegrass or Bentgrass varieties.

Best For: Homeowners with medium-sized lawns up to 5,000 square feet who want to tackle weeding and fertilizing in a single application, particularly those with compatible grass types like Bermudagrass, Fescue, and Zoysiagrass.

Pros:

• Combines weed control and fertilization into one efficient application, saving time and effort
• WeedGrip Technology targets over 50 common weeds including dandelions, clover, and plantain
• Compatible with most popular grass types and covers a substantial 5,000 square feet

Cons:

• Cannot be used on St. Augustinegrass, Bentgrass, and several other grass varieties
• Requires specific weather conditions (60°F-90°F) and timing restrictions for optimal effectiveness
• Application requires wet lawn beforehand and 24-hour restriction on watering or exposure to rain

7-0-20 Summer Lawn and Turf Stress Granular Fertilizer (45lb Bag)

Summer-stressed lawns suffering from heat damage, drought conditions, or nutrient depletion find exceptional recovery support through Yard Mastery’s 7-0-20 Summer Lawn and Turf Stress Granular Fertilizer. This 45-pound bag delivers targeted nutrition with 7% nitrogen for growth, 3% iron for deep green color, and 20% potash for stress resistance across 15,000 square feet. You’ll appreciate its gentle formula that won’t burn your grass during vulnerable summer months, making it safe for centipede, zoysia, and other lawn types. Customer reviews consistently highlight dramatic improvements, with brown lawns transforming to vibrant green within days of application, earning this product 4.6 stars from satisfied homeowners.

Best For: Homeowners with summer-stressed lawns suffering from heat damage, drought conditions, or nutrient depletion who need a gentle yet effective fertilizer that won’t burn grass during vulnerable periods.

Pros:

• Gentle formula that won’t burn grass during summer stress periods, making it safe for application when lawns are most vulnerable
• Fast-acting results with customers reporting dramatic transformation from brown to deep green grass within days of application
• Comprehensive nutrient blend with 7% nitrogen for growth, 3% iron for color enhancement, and 20% potash for stress resistance

Cons:

• Higher price point compared to cheaper alternatives available at big box stores
• Limited to 15,000 square feet coverage per 45-pound bag, requiring multiple bags for larger properties
• May require combination with additional products like chelated iron for optimal results according to some users

Simple Lawn Solutions Advanced 16-4-8 Balanced NPK Liquid Fertilizer (32 Ounce)

Homeowners seeking a versatile, ready-to-use solution for late summer lawn recovery will find Simple Lawn Solutions Advanced 16-4-8 Balanced NPK Liquid Fertilizer particularly effective for revitalizing stressed grass. This liquid formula delivers nitrogen for chlorophyll production and dense growth, phosphorus for root development, and potassium for overall plant health. The ready-to-spray bottle guarantees even distribution across all grass types, from Bermuda to Kentucky Bluegrass, making application straightforward for any homeowner. You’ll notice rapid greening within 24 hours when applied correctly, though careful attention to application rates prevents potential grass burning from overuse.

Best For: Homeowners with established lawns of any grass type who want a ready-to-use liquid fertilizer that provides rapid greening and addresses nutrient deficiencies without the hassle of mixing or measuring.

Pros:

• Ready-to-spray formula with even distribution makes application straightforward for all grass types including Bermuda, St. Augustine, Zoysia, and Kentucky Bluegrass
• Shows rapid results with visible greening within 24 hours when applied correctly
• Contains beneficial organic ingredients like seaweed and fish along with balanced NPK nutrients for comprehensive lawn health

Cons:

• Risk of burning grass if over-applied, requiring careful attention to application rates
• Some users report lawn damage from improper usage despite the ready-to-use format
• Limited guidance provided on supplemental nutrients that may be needed for optimal results

Ultimate 3-18-18 NPK Lawn Food Quality Liquid Fertilizer (32 Ounce)

Late summer lawn care demands strategic nutrition that prioritizes root development over excessive top growth, and Ultimate 3-18-18 NPK Lawn Food delivers precisely this balance through its high-phosphorus, high-potassium formula. This concentrated liquid fertilizer strengthens root systems while promoting turf hardiness, preparing your grass for fall’s challenges and winter dormancy ahead. You’ll appreciate the ready-to-use hose-end sprayer that covers 3,200 square feet, making application effortless across all grass types including Bermuda, St. Augustine, and Zoysia. The low nitrogen content prevents unwanted growth spurts while the elevated phosphorus and potassium levels enhance plant vigor and essential cellular functions for sustained lawn health.

Best For: Homeowners looking to strengthen their lawn’s root system and prepare grass for winter with a late-season fertilizer that works on all grass types without promoting excessive growth.

Pros:

• High phosphorus and potassium content specifically designed for late summer/fall application to enhance root development and turf hardiness
• Ready-to-use hose-end sprayer provides easy application covering 3,200 square feet with minimal effort
• Compatible with all grass types including Bermuda, St. Augustine, Zoysia, and others, making it versatile for different lawn varieties

Cons:

• Low nitrogen content may not address lawns needing immediate green-up or recovery from summer stress
• Limited to seasonal use (summer/fall only) rather than being a year-round fertilizer solution
• Requires adequate watering after application and should only be used on actively growing turf, limiting timing flexibility

Factors to Consider When Choosing Late Summer Fertilizer

When I help you select the right late summer fertilizer, I consider several critical factors that’ll determine your lawn’s success through fall and winter. Your specific grass type, whether cool-season or warm-season, directly influences the nutrient ratios you’ll need, particularly the balance of nitrogen, phosphorus, and potassium. I’ll also guide you through timing your application correctly, calculating proper coverage for your lawn size, and adjusting your approach based on current weather patterns.

Grass Type Compatibility

Since different grass varieties have distinct nutritional requirements and growth patterns, selecting the right fertilizer becomes crucial for achieving ideal lawn health in late summer. I recommend understanding your specific grass type before choosing any fertilizer formula. Cool-season grasses like Kentucky Bluegrass respond well to higher nitrogen levels during fall preparation, while warm-season varieties such as Bermuda and Zoysia thrive with potassium-rich formulations in late summer. You’ll find that products featuring WeedGrip Technology effectively control weeds across multiple grass types while supporting overall lawn vigor. I always emphasize avoiding fertilizers incompatible with your grass variety, particularly for sensitive types like St. Augustine and Bentgrass, which can suffer damage from inappropriate nutrient ratios or application timing.

Nutrient Balance Requirements

As temperatures reach their peak and your lawn faces mounting stress, achieving the proper nutrient balance becomes absolutely critical for maintaining healthy turf through late summer’s challenging conditions. I recommend focusing on fertilizers with lower nitrogen levels, which prevents excessive top growth that can lead to tissue burn in extreme heat. Your ideal nutrient ratio should emphasize potassium in a 2:1 ratio compared to nitrogen, enhancing drought resistance and preparing your grass for autumn stresses ahead. Don’t overlook phosphorus, especially if you’ve planted new grass this season, as it strengthens root development and improves nutrient uptake. I suggest conducting a soil test first to identify specific deficiencies, then selecting slow-release formulations that provide steady nutrition as temperatures cool.

Application Timing Considerations

Although many gardeners rush to fertilize their lawns during spring’s early excitement, I’ve found that strategic timing in late summer actually delivers far superior results for long-term turf health. The key lies in synchronizing your application with your grass’s natural growth cycles, when temperatures begin cooling but remain warm enough to promote active nutrient uptake.

I recommend targeting that sweet spot when nighttime temperatures drop into the 60s, yet daytime warmth still encourages root development. This timing allows your lawn to recover from summer stress while building resilience for winter dormancy. Weather monitoring becomes essential here, as you’ll want to avoid fertilizing before heavy rainfall that can wash away nutrients and reduce effectiveness, ultimately wasting your investment in lawn care.

Weather Condition Impact

Beyond timing your application perfectly, weather conditions will make or break your fertilizer’s performance, directly affecting how well your grass absorbs those essential nutrients. I’ve learned that temperature control is absolutely critical during late summer applications, since excessive heat can burn your lawn if you’re not careful with timing. You’ll want to verify soil temperatures stay above 60°F to stimulate proper root growth, but avoid applying during scorching afternoon heat. Rain and humidity become your best allies here, enhancing nutrient uptake when moisture levels are adequate for absorption. During drought conditions, I always recommend watering thoroughly before and after application, since dry soil severely limits fertilizer absorption and wastes your investment in lawn care.

Coverage Area Calculations

One critical mistake I see homeowners make involves miscalculating their lawn’s coverage area, which leads to uneven fertilization and disappointing results. I recommend starting by measuring your lawn’s total square footage, then subtracting hardscapes like driveways, patios, and walkways from that calculation. Most late summer fertilizers specify coverage areas ranging from 4,000 to 5,000 square feet per bag, depending on the product weight and formulation. You’ll find application rates clearly listed on fertilizer packaging, typically expressed as pounds per 1,000 square feet, which helps determine your total product needs. Understanding these specifications prevents over-fertilizing, which can cause lawn burn during late summer’s stress period, while ensuring adequate nutrient distribution for peak fall preparation and consistent green coverage.

On a final note

I’ve shared eight excellent fertilizer options that’ll help you maintain a vibrant, healthy lawn through late summer and into fall. Whether you choose a granular formula like Scotts WinterGuard or a liquid option like Simple Lawn Solutions, you’re investing in your yard’s long-term success. Remember to take into account your lawn’s specific needs, soil conditions, and coverage area when making your selection for best results.