Summer Lawn Care Tips

Summer lawn care is mostly about restraint. Cool season grasses are under real stress in heat and drought, and the routine that grew a thick lawn in spring will thin it out in July. The goal for the hottest weeks is not growth, it is survival with the root system intact.

Raise the Mowing Height

If you change one thing this summer, change this. Set the mower to the highest practical setting, usually around three to four inches for cool season grasses. Longer blades shade the soil surface, which keeps root zone temperatures down and slows evaporation, and they support a deeper root system that reaches moisture a scalped lawn cannot.

Long grass also shades out weed seedlings. Crabgrass in particular germinates in bright, warm soil, so a short lawn in summer is an open invitation.

Stick to the one third rule: never remove more than a third of the blade height in a single cut. Taking off more shocks the plant and forces it to spend stored energy regrowing leaf instead of holding on.

Water Deeply and Rarely

Frequent light watering is the most common summer mistake. It wets the top inch of soil, encourages roots to stay shallow where they cook first, and evaporates before it does much good.

Instead, water thoroughly and infrequently: aim for roughly one inch of water per week, delivered in one or two long sessions rather than daily sprinkles. Push a screwdriver into the soil after watering. If it slides in six inches easily, the water has gone deep enough.

Water early in the morning, ideally before 9am. Evening watering leaves blades wet overnight, which is how fungal disease gets established, and midday watering loses a large share to evaporation before it reaches the roots.

Let Cool Season Grass Go Dormant

Kentucky bluegrass, fescue and ryegrass are built to shut down in prolonged heat and drought. A brown, crisp looking lawn in August is usually dormant rather than dead, and it will green up again when temperatures drop and rain returns.

If you decide to let it go dormant, commit to it. The damaging pattern is watering just enough to break dormancy, then stopping, which forces the plant to spend reserves waking up and then leaves it exposed. Either water properly through the summer or give it about half an inch every two or three weeks purely to keep the crowns alive.

Sharpen the Blade

A dull mower blade tears grass rather than cutting it. Torn tips dry out and brown off, which is why a lawn can look faded a day after mowing even at the right height. Ragged wounds also heal slower and give disease an easier entry point. Sharpening once or twice a season is enough for most lawns.

Feed Carefully, or Not at All

Do not apply nitrogen fertiliser to a cool season lawn in the heat of summer. You are pushing soft top growth on a plant that has no spare energy for it, and quick release nitrogen on dry soil can scorch the grass outright.

Warm season grasses such as Bermuda and zoysia are the exception, since summer is their active growing period and a light feed suits them. For everything else, save the meaningful feed for early fall, which is when cool season grass does most of its root building.

Weeds and Grubs in Summer

Spot treat broadleaf weeds rather than blanket spraying a stressed lawn, and avoid herbicide entirely on days above roughly 85F, when it is more likely to damage the grass than the weed. Hand pulling after rain, while the soil is soft, is often faster than it sounds.

Grub damage tends to show in late summer as irregular brown patches that lift like a loose carpet because the roots have been chewed through. Check by peeling back a patch: more than about five or six grubs per square foot is worth treating. Fewer than that, and a healthy lawn will outgrow the damage.

Save Repairs for Fall

Overseeding, patching bare spots, aerating and dethatching all belong in early fall, not summer. Seed sown into hot, dry soil germinates poorly, and the seedlings that do appear rarely survive their first heat wave. Aerating a drought stressed lawn just opens up more surface area to dry out.

Note the bare patches now, then act on them when soil temperatures drop. Our complete guide to lawn care through the seasons sets out what each season is genuinely for.

Traffic and Shade

Grass under heat stress recovers slowly from wear, so move paddling pools, furniture and play equipment every few days rather than leaving them in one spot for weeks. Where a route gets walked constantly, the honest fix is a path rather than repeated reseeding: see our guide to building a gravel pathway in a weekend.

Shaded areas need less water than open lawn but also grow thinner, so raise the cut even higher there and accept lower density rather than fighting it.

A Quick Summer Schedule

• Weekly: mow high, only when the grass has grown enough to need it.
• Weekly: one deep watering of about an inch, early morning, or two half inch sessions.
• Monthly: walk the lawn for grub damage, disease patches and weed spread.
• Once per season: sharpen the mower blade.
• Not now: nitrogen feeding, overseeding, aerating, dethatching, hard renovation.

Frequently Asked Questions

How often should I water my lawn in summer?

Once or twice a week, deeply, totalling around one inch of water. Daily light watering keeps roots shallow and makes the lawn less able to handle heat, not more.

Is my brown summer lawn dead?

Usually not. Cool season grasses go dormant in heat and drought and green up when conditions improve. Tug a handful: if the crowns hold firm, it is dormant. If it pulls away easily with no white root tissue, that patch has died.

Can I put down grass seed in summer?

It is the worst time of year for it. Hot, dry soil gives poor germination and high seedling loss. Wait for early fall, when warm soil and cooler air give seed the best possible start.