Weed Control
Herbicide Surfactant vs Crop Oil: The Label Decides
Crop oil concentrate is 80–85% oil with only 15–20% surfactant in it. Not a stronger surfactant — a different product, and substituting can break the label.
Selective Grass Herbicide (sethoxydim, over-the-top of ornamentals)
Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz Review
★★★★☆ 4.2/5
our editor rating how we score4/5 from 535 shoppers at Amazon — their number, not ours.
$25–$32
Typical price · 8 oz concentrate; rates per label by site
Affiliate links — see our disclosure. Commissions never influence verdicts.
The consumer sethoxydim that is genuinely hard to find — and its own listing calls it something else.
Our Verdict
Worth reviewing for two reasons, and one of them is a warning about listings rather than about the product. Sethoxydim is a cyclohexanedione grass herbicide, the same class as clethodim, and UGA Extension names it among the options for bermudagrass in centipedegrass. It is also the active almost nobody can find at consumer scale — searching the chemistry name returns nothing, which is exactly the problem this bottle solves. Its label is EPA Reg. 7969-58-7401, a distributor label of BASF's Poast, at sethoxydim 18.0%, and it controls bermudagrass, crabgrass, foxtails, quackgrass and a long list of other grasses. What it is NOT is a lawn product. The label's framing is control of grassy weeds without injuring desirable plants — meaning ornamental beds and landscape areas, where the desirable plants are broadleaf. Sethoxydim kills grass, so on a lawn it is the opposite of selective. Read the site list before you buy it for a bermudagrass problem: if the bermudagrass is in your turf, this is the wrong shelf, and the fescue-labelled fluazifop product is the right one.
✅ Pros
- Sethoxydim at consumer scale, which is genuinely difficult to source — most sethoxydim is agricultural
- Distributor label of BASF's Poast, so the chemistry is the long-established one
- Bermudagrass, crabgrass, foxtails and quackgrass all on the grass list
- Different class from fluazifop only in detail, but a real alternative where fluazifop is restricted
⚠️ Cons
- NOT a lawn product — it kills grass, so its site is ornamental beds and landscape areas
- The Amazon listing names fluazifop-P-butyl as the active; the label says sethoxydim
- Do not apply on or around fruits, and a one-year pre-harvest restriction applies where relevant
- For bermudagrass in a fescue lawn this is the wrong product — see the fescue-labelled fluazifop instead
Product type
Selective Grass Herbicide (sethoxydim, over-the-top of ornamentals)
Active ingredient
Sethoxydim 18.0%
Price range
$25–$32
Coverage
8 oz concentrate; rates per label by site
Best for
Grassy weeds, including bermudagrass, coming up through ornamental and landscape beds
our editor rating
4.2 out of 5
Where our facts come from
Label read on the registrant's own PDF
EPA Reg. No. 7969-58-7401
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
Label read 2026-08-03 on the registrant's own site (the 16 oz sibling of this 8 oz pack, same registration). EPA Reg. 7969-58-7401 — a distributor product: BASF base registration 7969-58, which EPA PPLS lists as POAST HERBICIDE, sethoxydim 18%, sold under Voluntary Purchasing Group's company number 7401. Label active: SETHOXYDIM 18.0%. LISTING CONTRADICTION: the Amazon listing states the active is 'Fluazifop-P-butyl'. It is not. Sethoxydim and fluazifop are different actives in different chemical classes, and the listing would have had us file this as a third fluazifop product. Label framing is control of weedy grasses 'Without Injuring Desirable Plants' — i.e. ornamental and landscape sites, not turf. Grass list includes bermudagrass, crabgrass, foxtails, quackgrass, barnyardgrass, junglerice, lovegrass, seedling orchardgrass and broadleaf signalgrass. Restrictions include not applying on or around fruits and a one-year pre-harvest interval.
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.
Alabama
Alabama hub →Crabgrass
Application window: April–May and September, and check every label against centipede before it leaves the shelf
Arizona
Arizona hub →Crabgrass
Application window: March–May and during monsoon flushes; Celsius-type products handle 100°F+ windows
Arkansas
Arkansas hub →Crabgrass
Application window: Bounded by the label's temperature ceiling rather than the calendar — spring treatments finish before the June heat arrives, and nothing selective goes down again until September cools off
California
California hub →Crabgrass
Application window: March–May while weeds are young; avoid spraying drought-stressed turf in summer
Colorado
Colorado hub →Crabgrass
Application window: May–June and September; high-altitude sun makes stressed turf easy to injure, so spot-treat rather than blanket-spray
Connecticut
Connecticut hub →Crabgrass
Application window: Broadleaf sprays in May–June and again in September, when the weeds are moving sugars to the roots; skip July and August, when a stressed cool-season lawn takes the injury and the weed does not
Delaware
Delaware hub →Crabgrass
Application window: April to late May, then September into October. Skip July and August entirely: this is the transition zone, and a stressed tall fescue lawn takes the injury the weed shrugs off
Florida
Florida hub →Crabgrass
Application window: March–May and October–November; avoid applications above 85°F
Georgia
Georgia hub →Crabgrass
Application window: April to early June and September–October; avoid mid-summer sprays on stressed turf
Hawaii
Hawaii hub →Crabgrass
Application window: Year-round where the turf is actively growing, which is most of the time; the constraint is heat and drought stress on the leeward side rather than a dormant season
Idaho
Idaho hub →Crabgrass in the warmer southern valleysQuackgrass, a perennial grass with no selective answer inside a lawn
Application window: Late April into June, then September into October; skip the July and early August heat, which is also when UI's own fertilizer schedule goes quiet
Illinois
Illinois hub →CrabgrassQuackgrass
Application window: May–June and September; fall beats creeping charlie best
Indiana
Indiana hub →Crabgrass
Application window: October is the most effective month for broadleaf weeds; never apply above 80°F or to drought-stressed turf
Iowa
Iowa hub →Crabgrass
Application window: October, and October is most of it — but check the wind and the date against what is happening in the fields, because early-summer growth-regulator drift is a real seasonal risk here and your own spray carries the same way
Kansas
Kansas hub →Crabgrass
Application window: April into May and again in September–October; avoid July and August, when a tall fescue lawn here is already at its limit
Kentucky
Kentucky hub →Crabgrass
Application window: April–May and September–October; autumn is the knockout window for the wild garlic that defines a Kentucky winter lawn
Maine
Maine hub →Crabgrass (southern and coastal Maine more than the interior)
Application window: June, then a narrow late-August to mid-September window. Maine's usable autumn is the shortest in New England
Maryland
Maryland hub →Crabgrass
Application window: April–May and September–October; autumn is the knockout window for the ground ivy and violet the Piedmont is full of
Massachusetts
Massachusetts hub →Crabgrass
Application window: A narrow autumn is the real window here: late September into October, after the summer heat and before New England's early frost closes the season
Michigan
Michigan hub →Crabgrass
Application window: May–June and September; autumn is the stronger window for perennial broadleaf weeds
Minnesota
Minnesota hub →CrabgrassQuackgrass
Application window: Late May–June and September; autumn is the stronger window for perennial broadleaf weeds
Mississippi
Mississippi hub →Crabgrass
Application window: April–May and September, avoiding the midsummer heat restrictions on most labels
Missouri
Missouri hub →Crabgrass
Application window: April–May and September–October; skip summer sprays on drought-stressed fescue
Montana
Montana hub →Quackgrass, a perennial grass weed with no selective answer inside a lawnCrabgrass and foxtail in the warmer valleys and in thin ground
Application window: June, then late August into September. In a sub-100-day valley there is no third chance
Nebraska
Nebraska hub →Crabgrass
Application window: Late spring and again from late August through September, when perennial broadleaf weeds are moving reserves to the root
Nevada
Nevada hub →Crabgrass
Application window: March–April and October in the south; May and September in the north
New Hampshire
New Hampshire hub →Crabgrass (heaviest in the south, thinning northward)
Application window: Late May into June, then late August through September. The autumn window closes earlier here than anywhere else in southern New England
New Jersey
New Jersey hub →Crabgrass
Application window: May and September–October; autumn is the knockout window for perennial broadleaf weeds
New Mexico
New Mexico hub →Crabgrass in irrigated turf
Application window: Spring and early autumn; in the south skip the June heat entirely, and in the north the usable autumn window closes by early October
New York
New York hub →Crabgrass
Application window: May and September–October; autumn is the knockout window for perennial broadleaf weeds
North Carolina
North Carolina hub →Crabgrass
Application window: April–May and September–October; avoid spraying heat-stressed fescue in July–August
North Dakota
North Dakota hub →Foxtail and barnyardgrass in thin or disturbed groundQuackgrass, a perennial grass weed with no selective answer in a lawnCrabgrass, real but a smaller problem than further south
Application window: Early to mid-June, then late August into early September. There is no third opportunity
Ohio
Ohio hub →Crabgrass
Application window: May–June and September; fall applications hit dandelion taproots hardest
Oklahoma
Oklahoma hub →CrabgrassSandbur (the western sandy-soil weed that standard crabgrass preventers do not list)
Application window: Judged by wind before season: sustained wind is Oklahoma's normal condition, so the usable spray days are calm mornings in April, May and September rather than whole months
Oregon
Oregon hub →Crabgrass (east side and hot summers only)
Application window: March–May and September–October; the long mild shoulder seasons give more usable spray days than most states get
Pennsylvania
Pennsylvania hub →Crabgrass
Application window: May and September — fall is the knockout window for perennial broadleaf weeds
Rhode Island
Rhode Island hub →Crabgrass
Application window: Broadleaf work in May–June and again in September; the September pass is the one that holds, because the weed is moving reserves down
South Carolina
South Carolina hub →Crabgrass
Application window: April–May and September–October, and never above 90°F — centipedegrass is sensitive to 2,4-D both at spring green-up and in summer heat
South Dakota
South Dakota hub →Crabgrass and foxtail in thin or disturbed groundQuackgrass, a perennial grass weed with no selective answer inside a lawn
Application window: Early to mid-June, then late August into September, which is the pass that actually holds on perennial broadleaf weeds
Tennessee
Tennessee hub →Dallisgrass (a perennial the quinclorac that clears crabgrass will not touch)Crabgrass
Application window: April–May and September–October; skip sprays on drought-stressed summer fescue
Texas
Texas hub →Crabgrass
Application window: April–early June and September–October; avoid herbicides above 90°F
Utah
Utah hub →Crabgrass
Application window: May and September, avoiding the intense midsummer heat on the label
Vermont
Vermont hub →Crabgrass (a valley problem more than a hill-town one)
Application window: Late May through June, then a short late-August to mid-September window. Vermont's autumn window is the narrowest in New England
Virginia
Virginia hub →Crabgrass
Application window: April–May and September–October; skip sprays on heat-stressed fescue in July and August
West Virginia
West Virginia hub →Crabgrass
Application window: April into May and again in September–October. Skip July and August: this is transition-zone country and a heat-stressed tall fescue lawn absorbs the injury the weed does not
Wisconsin
Wisconsin hub →CrabgrassQuackgrass
Application window: Early to mid-fall is the favourable window for dandelion and other perennial broadleaf weeds
Wyoming
Wyoming hub →Quackgrass, a perennial grass with no selective answer inside a lawn
Application window: June, then late August into September. UW's own framing is useful: a slow-release application covers a 90 to 100 day growing season, which is roughly the entire Wyoming season
Common questions
Common Questions
How much does Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz cost?
Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz typically runs $25–$32, covering 8 oz concentrate; rates per label by site.
What does Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz treat?
Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz targets bermudagrass in landscape beds, crabgrass, quackgrass, foxtail, grassy weeds in ornamentals.
What is the active ingredient in Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz?
Sethoxydim 18.0%, registered under EPA Reg. No. 7969-58-7401.
What is the biggest downside of Hi-Yield Grass Killer Postemergence Grass Herbicide, 8 oz?
NOT a lawn product — it kills grass, so its site is ornamental beds and landscape areas
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