End-of-Summer Lawn Care Guide
As summer winds down and the cooler weather creeps in, your lawn enters a critical transition period. While it might be tempting to coast through the last warm days, what you do now can make or break your lawn's health come fall—and even set the stage for a strong spring.
For lawn care DIYers, late August through September is go-time. Here’s your comprehensive guide to everything your lawn needs before fall hits: weed control, fertilizing, grub treatment, soil health, and more.
Fall is prime time for seeding and overseeding—cooler temps, more consistent rain, and less weed pressure create ideal growing conditions. Late-summer is a good time to prep for any upcoming seeding projects.
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Dethatch if thatch is thicker than ½ inch.
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Core aerate to relieve compaction and improve seed-to-soil contact.
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Choose a high-quality grass seed that matches your region and sun/shade conditions.
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Topdress with compost or quality topsoil to improve germination and soil structure.
When to seed: Typically 5–6 weeks before your area's first expected frost.
Grubs are one of the most destructive lawn pests, feeding on grassroots and leaving brown patches that peel up like carpet.
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Late summer to early fall is the best time to treat for grubs, as they’re young and closer to the surface.
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Use a curative insect control product like DuoCide® for existing infestations.
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For prevention next year, consider a preventative treatment like GrubOut Plus Lawn Food 17-0-3.
Signs of grubs: Increased skunk, mole or bird activity, brown patches, and soft, spongy turf.
Summer weeds like spurge and clover have likely made themselves at home. Now is the perfect time to tackle them—before they go to seed.
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Use a selective post-emergent herbicide to target broadleaf weeds like dandelions and clover without harming your grass, such as Surge® Weed & Feed 16-0-9 or Weed & Feed 24-0-16.
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Apply a weed and feed product only if your lawn still needs nitrogen and you're not planning to overseed in the next 4–6 weeks.
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Avoid a “weed and feed” if you’re seeding soon—it can prevent new seed from germinating.
Pro Tip: Always check the label to avoid applying herbicides too close to seeding or overseeding.
End-of-summer fertilizing sets the foundation for fall growth and winter resilience.
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Use an slow-release fertilizer with moderate nitrogen and balanced phosphorus and potassium, such as Core™ 24-6-12.
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Avoid high-nitrogen quick-release fertilizers now—they can push too much top growth and weaken roots.
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If you plan to seed, opt for a starter fertilizer with higher phosphorus, such as New Lawn Starter 20-27-5 or EcoFusion™ Starter 16-21-4 to encourage root growth.
Don’t fertilize too late: Fertilizing too close to winter can lead to frost damage and disease susceptibility.
Your lawn needs more than just N-P-K. Micronutrients like iron, manganese, and zinc can improve color, growth, and stress resistance.
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Look for a micronutrient blend, such as Micronutrient Supplement or Lawn I.V., if your lawn is pale or sluggish despite proper care.
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A soil test can help you determine if your lawn needs additional micronutrients.
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Chelated iron can give a deep green boost without excessive growth.
Water in micronutrients thoroughly, especially if applying during warm days.
Healthy soil is the foundation of a healthy lawn. Late summer is a great time to give your soil a check-up.
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Test your soil pH and nutrients using a soil test kit.
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Most grasses prefer a pH of 6.0 to 7.0.
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Add NutraLime OP® Hi-Mag Lime if your soil is too acidic or Elemental Sulfur pH Down if it’s too alkaline.
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Compost topdressing, as well as Humic DG™ and BioChar DG™, helps improve soil structure and microbial activity.
Goal: Build a living, breathing soil system that supports healthy grass from the roots up.
As temps drop, your watering schedule should change too.
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Reduce frequency, but deepen each watering—aim for 1 inch per week.
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Morning watering is still best to prevent fungal issues.
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Newly seeded lawns may require light, frequent watering until germination.
Late summer is often overlooked in the lawn care calendar, but it’s actually one of the most impactful times to take action. Whether you’re chasing a lush fall lawn or laying the groundwork for spring, what you do now matters.
Take advantage of the season—plan smart, feed right, and treat issues before they get out of hand. Your lawn will thank you in the coming months.
