broadleaf weed · perennial

How to Kill Thistle (Canada and Bull)

Cirsium arvense

Herbicide sprayhard to controlLawn & beds

What Thistle (Canada and Bull) looks like

Spiky, deeply-lobed purple leaves with prickly margins and purple-pink thistle flowers; grows 2–4 feet tall.

📸

Not sure if it's Thistle (Canada and Bull)?

Snap a photo — our free AI tells you in seconds. No app needed.

Best approach: Herbicide spray

Canada thistle has an extensive root system — digging usually fails because any root fragment left behind regrows. Spray with triclopyr or glyphosate (spot-treat) for best results. Wear thick gloves due to spines.

Chemical treatment

Spot-treat with glyphosate when actively growing in spring or early summer, or use a strong broadleaf herbicide (2,4-D + dicamba or triclopyr) in fall. Repeat as needed.

Non-chemical management

Remove flowers before they set seed; maintain turf density to prevent thistle establishment.

How to stop Thistle (Canada and Bull) coming back

Remove flowers before they set seed; maintain turf density to prevent thistle establishment.

Recommended products for Thistle (Canada and Bull)

BioAdvanced All-In-One Weed & Feed (22-0-4)

Quinclorac 18.92%granular$25-$40 (12 lb bag, covers 5,000 sq ft)
View on Amazon

Scotts Turf Builder Southern Triple Action

Pendimethalin + broadleaf herbicide + fertiliser (formulated for warm-season grass)granular$55–$70
View on Amazon

Scotts Turf Builder Southern Triple Action

Pendimethalin + broadleaf herbicide + fertiliser (formulated for warm-season grass)granular$55-$65 (13.32 lb bag, covers 4,000 sq ft)
View on Amazon

Scotts Turf Builder Triple Action1

Pendimethalin, Dicambagranular$30-$45 (11.31 lb bag, covers 4,000 sq ft)
View on Amazon

As an Amazon Associate, Measure Lawn earns from qualifying purchases.

Stop fighting weeds one by one →

Get your free 12-month AI lawn care plan

A thick, healthy lawn is the best weed killer there is. Measure your yard on a satellite map in 30 seconds — we'll build a personalised schedule (fertiliser, seed, mowing, weed control) so thistle (canada and bull) doesn't come back.

Measure my lawn — it's free →

FAQ

What does Thistle (Canada and Bull) look like?

Spiky, deeply-lobed purple leaves with prickly margins and purple-pink thistle flowers; grows 2–4 feet tall.

What's the best way to kill Thistle (Canada and Bull)?

Herbicide spray. Canada thistle has an extensive root system — digging usually fails because any root fragment left behind regrows. Spray with triclopyr or glyphosate (spot-treat) for best results. Wear thick gloves due to spines.

Is Thistle (Canada and Bull) hard to get rid of?

Thistle (Canada and Bull) is rated hard to control. It usually requires multiple applications and a consistent plan.

How do I stop Thistle (Canada and Bull) coming back?

Remove flowers before they set seed; maintain turf density to prevent thistle establishment.

Other broadleaf weeds

Dandelion

moderate · annual

White Clover

moderate · annual

Chickweed (Common and Mouse-ear)

hard · annual

Henbit

moderate · annual

See every weed we cover:

Full weed guidePhoto identifierLawn care calendar