Diagnose. Treat. Grow.

Expert lawn care guides powered by science and built for healthier American lawns. Stop guessing and give your turf exactly what it needs.

Diagnose My Lawn — Free Browse Guides

Extension sources cited: 392Extension sources cited
States with local data: 50States with local data
In-depth guides: 172In-depth guides

Suburban homeowner standing on a healthy green lawn in front of a house, holding a phone showing a lawn assessment checklist

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Tailored to your state's climate

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What's wrong with your lawn?

Start with the most common problems American homeowners face — or run the assessment for a personalized answer.

Weed Control

Kill dandelions, clover and crabgrass — without killing your grass.

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Lawn Diseases

Diagnose brown patch, fungus and dollar spot before they spread.

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Yellow Grass

Nine reasons your grass is turning yellow — and how to fix each one.

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Fertilizer Problems

Burned stripes, no response, wrong timing? Get feeding right.

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Answer a few questions about what you're seeing — patch shape, color, weather, a ten-second pull test — and get an automated report with the closest documented match, a treatment plan and a recovery timeline for your state.

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Symptom matching, not image analysis — and your photo never leaves your device.

Lawn Care CalendarYour season-by-season schedule, by state and grass type Robot Mower FinderWhich robotic mower fits your size, slope and grass — draw your yard and watch it cut

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Our most complete, most useful playbooks.

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A dandelion in a lawn whose outer leaves have browned and collapsed while fresh green leaves regrow from the centre of the crown, a hand pump sprayer on the grass behind it

Weed Control

Why Didn't My Weed Killer Work? Six Causes, One Is the Product

Purdue: hard water can inactivate glyphosate, and more water in the tank can make it worse. Start from what you saw, not from which brand you bought.

August 3, 2026

A soil sample being taken from a lawn: a hand trowel, a plug of soil standing upright beside the open hole it came from, and an open brown paper bag holding some of the soil

Fertilizer

Lawn Soil pH: When to Lime, When to Add Sulfur

Lawn soil pH decides whether lime or sulfur is the fix — and the right answer inverts between Georgia and Arizona. What the soil test number means.

July 29, 2026

A hand holding a tuft of straw-coloured grass pulled free of the lawn, its exposed roots short, sparse and brown rather than white and fibrous, with the hollow it came from below

Lawn Diseases

Spring Dead Spot and Summer Patch: Why Sprays Fail

Spring dead spot and summer patch attack roots, not leaves — so they mimic drought, shrug off leaf sprays, and return to the same spot bigger each year.

July 29, 2026

Fresh from the field

Latest Articles

Science-backed answers to real lawn problems, each one citing its sources.

An open irrigation valve box in a lawn on a frosty autumn morning with an air compressor hose coupled to the blow-out fitting beside it, frost on the surrounding grass and a sprinkler head visible in the background, with the words “80 PSI, OR 50” set across the top of the frame

Lawn Care Guides

How to Winterize a Sprinkler System: 80 PSI, or 50

Colorado State puts blow-out pressure at 40 to 80 psi — 80 max for rigid PVC, 50 for polyethylene. And two backflow devices must never see compressed air at all.

September 7, 2026

A warm-season lawn in late autumn split down the middle: dormant straw-tan bermudagrass on one side and bright green overseeded ryegrass on the other, with a walk-behind spreader standing on the line between them and the words “5 LB OR 15” set across the top of the frame

Grass Types

Overseeding Bermuda With Ryegrass: 5 lb or 15?

Clemson says 5 lb per 1,000 sq ft. Arizona says 12 to 15. Both are right, and the gap is what winter overseeding is for — plus the spring bill nobody quotes.

September 7, 2026

An oscillating sprinkler running on a suburban front lawn in low early-morning light with the shadow line of the house still across half the grass, a mechanical dial hose timer screwed onto the spigot in the foreground, and the words “TWO LEGAL WINDOWS” set across the top of the frame

Lawn Care Guides

Lawn Watering Restrictions: Keeping Grass Alive

Your city assigns the days and bans the hours. How to hit a weekly inch in two legal windows, and why cycle-and-soak is the trick.

September 2, 2026

A homeowner in gloves standing on their own front lawn holding a plain unlabelled handheld sprayer bottle, while a larger backpack sprayer stands unused on the driveway behind them beside a white pickup, and the words “WHO HOLDS IT” set across the top of the frame

Weed Control

Do You Need a License to Spray Your Own Lawn?

A pesticide applicator license turns on who holds the sprayer, not what is in it. What EPA restricts, and which state agency decides the rest.

September 2, 2026

Fertilizer

Phosphorus Fertilizer Laws: What You Can Legally Buy

Fifteen states restrict phosphorus lawn fertilizer by statute. Which bag is legal where you live, and why a soil test is the only thing that unlocks the other one.

September 2, 2026

A gardener raking a thin layer of dark finished compost across a prepared backyard vegetable bed, with a steel ruler standing upright in the bed for scale and a wheelbarrow of the same compost at the edge of frame, and the words “A QUARTER INCH” set across the top of the frame

Garden Guides

Compost for a Vegetable Garden: How Much Is Too Much

Utah State mixes an inch in before planting. Colorado State maintains at a quarter inch a year. The popular figure is neither, and it accumulates.

August 26, 2026

Find what your lawn needs this month, where you live

Pick your state on the map and get the tasks for the current season, the weeds and diseases active there now, and the guides written for your grass.

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Built for American lawns

Lawn care that knows your ZIP code

A Florida St. Augustine lawn and an Ohio bluegrass lawn have almost nothing in common. Every guide here adapts to your state's USDA zones, soil profile, disease and weed pressure, application windows and local fertilizer regulations.

states live: 50states live
conditions covered: 23conditions covered
US-focused: 100%US-focused

Alabama

Centipede · Zones 7a–9a

Alaska

Kentucky Bluegrass · Zones 1a–8b

Arizona

Bermuda · Zones 8a–10a

Arkansas

Bermuda · Zones 6b–8b

California

Tall Fescue · Zones 8a–10b

Colorado

Kentucky Bluegrass · Zones 4b–7a

Connecticut

Kentucky Bluegrass · Zones 6a–7b

Delaware

Tall Fescue · Zones 7a–7b

Florida

St. Augustine · Zones 8a–11a

Georgia

Bermuda · Zones 7a–9a

Show 40 more states

Hawaii

Bermuda · Zones 9a–13a

Idaho

Kentucky Bluegrass · Zones 3b–7b

Illinois

Kentucky Bluegrass · Zones 5a–6b

Indiana

Kentucky Bluegrass · Zones 5b–6b

Iowa

Kentucky Bluegrass · Zones 4b–6a

Kansas

Tall Fescue · Zones 6a–7a

Kentucky

Turf-Type Tall Fescue · Zones 6a–7a

Louisiana

St. Augustine · Zones 8a–9b

Maine

Kentucky Bluegrass · Zones 3b–6a

Maryland

Turf-Type Tall Fescue · Zones 5b–8a

Massachusetts

Kentucky Bluegrass · Zones 5b–7a

Michigan

Kentucky Bluegrass · Zones 4b–6b

Minnesota

Kentucky Bluegrass · Zones 3a–5a

Mississippi

Bermuda · Zones 7b–9a

Missouri

Turf-Type Tall Fescue · Zones 5b–7a

Montana

Kentucky Bluegrass · Zones 3a–6b

Nebraska

Kentucky Bluegrass · Zones 4b–6a

Nevada

Tall Fescue · Zones 5a–9a

New Hampshire

Kentucky Bluegrass · Zones 3b–6b

New Jersey

Turf-type Tall Fescue · Zones 6a–7b

New Mexico

Bermuda · Zones 4b–9a

New York

Kentucky Bluegrass · Zones 4a–7b

North Carolina

Tall Fescue · Zones 6a–8b

North Dakota

Kentucky Bluegrass · Zones 3b–4b

Ohio

Kentucky Bluegrass · Zones 5b–6b

Oklahoma

Bermuda · Zones 6a–8a

Oregon

Perennial Ryegrass · Zones 5a–9a

Pennsylvania

Kentucky Bluegrass · Zones 5b–7a

Rhode Island

Kentucky Bluegrass · Zones 6b–7b

South Carolina

Centipedegrass · Zones 7a–9a

South Dakota

Kentucky Bluegrass · Zones 4a–5b

Tennessee

Tall Fescue · Zones 6a–8a

Texas

Bermuda · Zones 6b–9b

Utah

Kentucky Bluegrass · Zones 4b–8a

Vermont

Kentucky Bluegrass · Zones 4a–6a

Virginia

Tall Fescue · Zones 5b–8a

Washington

Perennial Ryegrass · Zones 6b–8b

West Virginia

Tall Fescue · Zones 5b–7a

Wisconsin

Kentucky Bluegrass · Zones 3b–5b

Wyoming

Kentucky Bluegrass · Zones 4a–5b

0 more states

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Diagnose. Treat. Grow.

What's wrong with your lawn?

Weed Control

Lawn Diseases

Yellow Grass

Fertilizer Problems

Find out what's actually wrong with your lawn

Keep it on your home screen

Featured Guides

Why Didn't My Weed Killer Work? Six Causes, One Is the Product

Lawn Soil pH: When to Lime, When to Add Sulfur

Spring Dead Spot and Summer Patch: Why Sprays Fail

Latest Articles

How to Winterize a Sprinkler System: 80 PSI, or 50

Overseeding Bermuda With Ryegrass: 5 lb or 15?

Lawn Watering Restrictions: Keeping Grass Alive

Do You Need a License to Spray Your Own Lawn?

Phosphorus Fertilizer Laws: What You Can Legally Buy

Compost for a Vegetable Garden: How Much Is Too Much

Find what your lawn needs this month, where you live

Lawn care that knows your ZIP code

Seasonal lawn reminders, on time