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Systemic DMI fungicide concentrate (Group 3)
Atticus Gravex 20 EW Fungicide, 16 oz Review
★★★★☆ 4/5
our editor rating how we score4.4/5 from 341 shoppers at Amazon — their number, not ours.
$32–$45
Typical price · 1.2 fl oz per 1,000 sq ft on residential turf — a 16 oz bottle covers roughly 13,000 sq ft
Affiliate links — see our disclosure. Commissions never influence verdicts.
A straight myclobutanil concentrate whose label actually carries residential turf — and which is NOT a rotation partner for the propiconazole most homeowners already own.
Our Verdict
Worth owning for one specific reason and worth understanding for another. The reason to own it: it is a genuine systemic DMI at 19.7% whose label explicitly covers established residential turfgrass, at 1.2 fl oz per 1,000 sq ft — most homeowner fungicide options are either a granular or a hose-end at a fraction of the concentration, and this is the professional formulation with the home lawn on the label rather than off it. The reason to understand it: the label classifies it as a Group 3 sterol demethylation inhibitor and instructs that after two consecutive applications of Gravex 20 EW, another myclobutanil product, or another DMI, you rotate to a fungicide with a different mode of action. Propiconazole is also a DMI. So alternating this with the propiconazole bottle on the shelf is not rotation, it is the same group twice — the real rotation partner is the azoxystrobin granular, which is Group 11. One more thing on the label worth reading before you buy: myclobutanil is known to leach through soil into groundwater under certain conditions, which is a real consideration on sandy soil or over a shallow water table.
✅ Pros
- Residential turfgrass is on the label, not merely implied
- 19.7% concentrate — a bottle treats a large area
- Systemic, protectant AND curative per the label
- Label states its FRAC group and its own rotation rule, which few consumer labels do
⚠️ Cons
- Same Group 3 as propiconazole — not a rotation pair with it
- Label warns myclobutanil can leach to groundwater under some conditions
- Nassau and Suffolk Counties, New York cap the annual rate
- Residential rate is capped lower than the commercial rate on the same label
Product type
Systemic DMI fungicide concentrate (Group 3)
Active ingredient
Myclobutanil 19.7%
Price range
$32–$45
Coverage
1.2 fl oz per 1,000 sq ft on residential turf — a 16 oz bottle covers roughly 13,000 sq ft
Best for
A homeowner who wants a concentrate rather than a hose-end, and who is rotating it against azoxystrobin rather than against propiconazole
our editor rating
4 out of 5
Where our facts come from
Label read on the registrant's own PDF
EPA Reg. No. 91234-283
We read the printed label published by the company that holds the registration. EPA hosts no PDF for this one, so this is the best available text.
What we found when we read it
Full specimen label read 2026-08-08 on Atticus's own site. EPA Reg. No. 91234-283, myclobutanil 19.7%, other ingredients 80.3%. The label states its own resistance class — 'Gravex 20 EW belongs to the sterol demethylation inhibitor (DMI) class of fungicides and is classified as a Group 3 fungicide' — and its own rotation rule: after two consecutive applications of Gravex 20 EW, another myclobutanil product, or another DMI, rotate to a labelled fungicide with a different mode of action. THAT MATTERS FOR OUR CATALOGUE: our other lawn DMI is propiconazole, so the two are the same group and are not a rotation pair; azoxystrobin (Group 11) is. RESIDENTIAL TURF IS ON THE LABEL and is rated separately from commercial: non-residential turfgrass runs to 2.4 fl oz per 1,000 sq ft while residential is 1.2 fl oz per 1,000 sq ft — the same commercial-higher-than-residential pattern found on the Ike's sandbur/crabgrass preventer label. STATE RESTRICTION: 'For Nassau and Suffolk Counties in New York State, DO NOT apply more than 3.43 fl oz of Gravex 20 EW per 1000 sq ft per year (1.95 lb ai per acre)', with a separate cap of no more than 5 applications per year. The label also carries a groundwater advisory: 'Myclobutanil is known to leach through soil into groundwater under certain conditions as a result of label use.'
Where this page and the container disagree, the container wins — the label is the legal authority on rates and restrictions. How to read one yourself.
Where This Product Matters
Matched against each state's actual disease, weed and pest pressure.
Arizona
Arizona hub →Rust (winter ryegrass)
Arkansas
Arkansas hub →Brown patch (tall fescue in the Ozarks)Spring dead spot (bermuda)
California
California hub →Brown patch (fescue under summer night irrigation)AnthracnoseRust (shaded, underfed lawns)
Colorado
Colorado hub →Powdery mildew (shaded bluegrass)
Connecticut
Connecticut hub →Red thread (the New England signature — pink threads on ryegrass and fine fescue in a cool wet spring, and it reads as a nitrogen shortage more than an infection)Brown patch (July and August on tall fescue, once the nights stop cooling off)
Delaware
Delaware hub →Brown patch — the defining disease of a Delaware tall fescue lawn, because humid nights that never drop below the high 60s are the normal July here rather than the exceptionGray leaf spot (tall fescue and perennial ryegrass, late summer, and it kills a stand faster than brown patch does)
Georgia
Georgia hub →Spring dead spot (bermuda)
Hawaii
Hawaii hub →Large patch and brown patch (Rhizoctonia) on zoysia and St. Augustine, running whenever warm humid conditions persist — which on the windward side is most of the year
Indiana
Indiana hub →Red thread (slow-growing lawns, late spring)Rust (slow-growing lawns, August through October)
Kansas
Kansas hub →Brown patch (Rhizoctonia solani) — the tall fescue killer here, running when temperatures pass 80°F with high humidity and high nitrogen, and capable of taking a stand out in a long hot humid stretchSpring dead spot on bermudagrass
Kentucky
Kentucky hub →Brown patch (tall fescue's summer killer statewide)Spring dead spot (bermuda in the west)
Maine
Maine hub →Red thread on ryegrass and fine fescue in a cool wet spring, which reads as a nitrogen shortage more than an infectionBrown patch — a southern-coast problem, uncommon inland and north
Maryland
Maryland hub →Brown patch (tall fescue's July and August killer statewide)Red thread (cool wet springs)
Massachusetts
Massachusetts hub →Brown patch (tall fescue in a humid coastal July)
Michigan
Michigan hub →Red thread
Missouri
Missouri hub →Brown patch (tall fescue's July and August killer)Spring dead spot (bermuda in the south)
Nebraska
Nebraska hub →Leaf rust on bluegrass in late summer, which turns shoes orange before anyone notices the lawn
Nevada
Nevada hub →Anthracnose on drought-stressed turf
New Hampshire
New Hampshire hub →Red thread (cool wet springs on ryegrass and fine fescue, and it reads as a nitrogen shortage)Brown patch (a Seacoast and southern-tier problem more than a North Country one)
New Jersey
New Jersey hub →Brown patch (tall fescue in humid July weather)Red threadRust (late-summer, underfed lawns)
New Mexico
New Mexico hub →Spring dead spot on bermudagrass, appearing as the lawn greens up
New York
New York hub →Red threadBrown patch (tall fescue and ryegrass in humid August weather)
⚖️ The label caps the annual rate in Nassau and Suffolk Counties: do not apply more than 3.43 fl oz per 1,000 sq ft per year (1.95 lb ai per acre). That is a Long Island rate limit rather than a prohibition — the rest of New York is unaffected.
North Carolina
North Carolina hub →Brown patch (the #1 tall fescue killer)Spring dead spot (Bermuda)
North Dakota
North Dakota hub →Leaf rust on bluegrass late in the season
Ohio
Ohio hub →Red threadRust (late summer on underfed lawns)
Oklahoma
Oklahoma hub →Spring dead spot (the bermuda disease Oklahoma winters create — patches that never green up in April)Brown patch (tall fescue in the northeast)
Oregon
Oregon hub →Red threadRustAnthracnose
Pennsylvania
Pennsylvania hub →Red thread on underfed lawns in a cool wet MayPowdery mildew (bluegrass under the state's heavy tree cover)Brown patch (tall fescue in a humid July)
Rhode Island
Rhode Island hub →Red thread (the fine-fescue and ryegrass disease of a cool wet Rhode Island spring — it reads as low nitrogen more than as an infection)Brown patch (humid bay nights are what make it a Rhode Island problem rather than an occasional one)Anthracnose (URI works on fungicide-resistant strains of it with UMass, which tells you how established it is in this corner of New England)
South Carolina
South Carolina hub →Brown patch (tall fescue in the Upstate)
South Dakota
South Dakota hub →Leaf rust on bluegrass late in the season
Tennessee
Tennessee hub →Brown patch (tall fescue's summer nemesis statewide)Spring dead spot (Bermuda)
Texas
Texas hub →Brown patch / large patchSpring dead spot (Bermuda)
Vermont
Vermont hub →Red thread (cool wet spring on ryegrass and fine fescue, reading as a nitrogen shortage)Brown patch — real in the Champlain Valley and the southern river valleys, uncommon at elevation
Virginia
Virginia hub →Brown patch (tall fescue's summer nemesis here)Spring dead spot (bermuda)
Washington
Washington hub →Red thread (the signature western Washington disease, fall through spring)
West Virginia
West Virginia hub →Brown patch — the defining disease of a West Virginia tall fescue lawn, driven by humid valley nights that never cool off in JulyGray leaf spot on tall fescue and perennial ryegrass in late summer, which takes a stand out faster than brown patch doesRed thread in a cool wet spring, reading as a nitrogen shortage more than an infection
Wisconsin
Wisconsin hub →Red thread
Common questions
Common Questions
How much does Atticus Gravex 20 EW Fungicide, 16 oz cost?
Atticus Gravex 20 EW Fungicide, 16 oz typically runs $32–$45, covering 1.2 fl oz per 1,000 sq ft on residential turf — a 16 oz bottle covers roughly 13,000 sq ft.
What does Atticus Gravex 20 EW Fungicide, 16 oz treat?
Atticus Gravex 20 EW Fungicide, 16 oz targets Brown patch, Anthracnose, Red thread, Rust, Spring dead spot, Powdery mildew.
What is the active ingredient in Atticus Gravex 20 EW Fungicide, 16 oz?
Myclobutanil 19.7%, registered under EPA Reg. No. 91234-283.
What is the biggest downside of Atticus Gravex 20 EW Fungicide, 16 oz?
Same Group 3 as propiconazole — not a rotation pair with it
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