Spectracide vs Ortho Weed Killer: Which One Should You Spray?
Updated October 14, 2026
Spectracide and Ortho sit next to each other on every garden-center shelf, and the bottles make the same promises: kills the weeds, not the lawn. Read the active ingredients box and you find out why. Spectracide Weed Stop for Lawns Concentrate2 lists 2,4-D, mecoprop-p, dicamba and sulfentrazone. Ortho WeedClear Weed Killer for Lawns Concentrate lists 2,4-D, mecoprop-p and dicamba. Three of the four ingredients are the same growth-regulator herbicides, so on dandelions, clover, chickweed and plantain the two sprays behave a lot alike.
The real differences are smaller and more useful. Sulfentrazone is what puts yellow nutsedge on the Spectracide label. The rates also split by grass: on St. Augustine, Spectracide mixes at 0.75 fl oz per gallon and Ortho at 1 fl oz. Both brands sell a separate crabgrass bottle with quinclorac, and both crabgrass bottles are off-limits on St. Augustine, centipede and bahia. The details below come from the current labels, which we cover rate by rate in our Spectracide Weed Stop mixing guide and our Ortho WeedClear instructions. If the bottle in your hand says something different, the bottle wins.
Quick verdict
Spectracide Weed Stop for Lawns wins when yellow nutsedge is in the mix or you want the lowest St. Augustine rate. Ortho WeedClear Weed Killer for Lawns wins for plain broadleaf weeds if you liked Weed B Gon. For crabgrass, each brand has a separate quinclorac bottle.
Spectracide Weed Stop for Lawns vs Ortho WeedClear Weed Killer for Lawns: at a glance
Active ingredients
Yellow nutsedge on the label
Crabgrass
Rate, cool-season grass
Rate, Bermuda and centipede
Rate, St. Augustine
Max per application
Repeat spray
Temperature
Rain and watering
Reseeding after spraying
Older bottles
Best for
APick Spectracide Weed Stop for Lawns if...
- Yellow nutsedge is growing alongside your dandelions and clover, and you want one spray for both.
- You have St. Augustine (not Floratam or Bitterblue) and want the lighter 0.75 fl oz per gallon label rate.
- You want to re-check results in about two weeks instead of waiting a month.
- You are fine checking which Weed Stop formula you bought before mixing, since the rates differ.
BPick Ortho WeedClear Weed Killer for Lawns if...
- Your weeds are the usual broadleaf crowd (dandelion, clover, chickweed, plantain) with no nutsedge.
- Weed B Gon worked for you before: WeedClear Weed Killer for Lawns carries the same EPA registration and actives.
- You want a two-rate label (northern and southern grasses) that is hard to mix wrong.
Get your seasonal lawn care calendar for your ZIP
Every task, from feeding to weed control to aeration, has a window that shifts by region. Add your ZIP and we will email your 12-month lawn calendar right away, starting with this month.
Seasonal reminders and tips. No spam. Unsubscribe anytime.
Frequently asked questions
Is Spectracide or Ortho better for killing weeds in the lawn?
For common broadleaf weeds like dandelion, clover and chickweed they perform about the same, because both concentrates are built on 2,4-D, mecoprop-p and dicamba. Spectracide Weed Stop for Lawns Concentrate2 adds sulfentrazone, which puts yellow nutsedge on its label, so it is the better pick when sedge is part of the problem. Ortho WeedClear Weed Killer for Lawns is the better pick if you want the plain Weed B Gon formula.
Is Ortho WeedClear the same as Weed B Gon?
The concentrate is. Ortho WeedClear Weed Killer for Lawns Concentrate carries EPA Reg. No. 239-2744, and EPA lists that registration with the same three actives at the same percentages as the Weed B Gon concentrate: 2,4-D, mecoprop-p and dicamba. Ortho sells its lawn weed killers under the WeedClear name now. If you still have an old Weed B Gon bottle, use the rate printed on that bottle.
Which kills crabgrass, Spectracide or Ortho?
Neither of the standard lawn concentrates compared here kills crabgrass. Each brand sells a separate crabgrass bottle that adds quinclorac: Spectracide Weed Stop for Lawns Plus Crabgrass Killer and Ortho WeedClear Lawn Weed Killer (the North version). Both work only on young crabgrass: the Spectracide label targets it before it reaches 3 to 4 inches, and the Ortho label before 4 inches. Both are off-label on St. Augustine, centipede and bahia lawns.
Can I use Spectracide or Ortho on St. Augustine grass?
Yes, with the standard broadleaf concentrates at the southern rate. Spectracide Weed Stop for Lawns Concentrate2 mixes at 0.75 fl oz per gallon on St. Augustine and excludes Floratam and Bitterblue. Ortho WeedClear Weed Killer for Lawns mixes at 1 fl oz per gallon on southern grasses and excludes Floratam, bentgrass and carpetgrass. Do not use either brand's crabgrass bottle on St. Augustine.
Which one is rainproof faster?
Neither concentrate label gives you a short rain window to rely on. The current Spectracide Concentrate2 label prints no rainproof hour count and targets a dry 24-hour forecast. Ortho markets its bottles as rainproof in 1 hour, but the Weed Killer for Lawns label says not to apply if rain is expected within 24 hours and to wait 12 hours before watering. Plan on a dry day either way.
Can I mix Spectracide and Ortho together or spray them back to back?
No. They share the same core herbicides, so stacking them doubles the 2,4-D, mecoprop-p and dicamba the lawn gets, which risks grass injury without killing weeds any faster. Pick one product, spray at its label rate, and wait out its re-treatment interval before spraying again.
How long after spraying can I reseed?
The Spectracide Concentrate2 label allows reseeding three to four weeks after spraying, and the Ortho WeedClear concentrate labels say to wait four weeks. If you are overseeding this fall, spray first, wait four weeks, then seed.