Dandelions: identify it, treat it, keep it out
Dandelions are broadleaf perennials with a taproot that can reach ten inches deep, which is why mowing the flowers off never kills the plant. Fall is the best kill window, when the plant pulls herbicide down into the root along with winter reserves.
How to identify dandelions
- Bright yellow flowers on smooth, hollow stems in spring and fall
- White puffball seed heads that scatter in wind
- Deeply toothed leaves in a flat rosette at ground level
- Regrows from the same spot after mowing or hand-pulling that snaps the taproot
Don't confuse it: Catsear (false dandelion) looks nearly identical in flower but has hairy leaves and branched, solid stems.
Not sure this is your weed? Snap a photo and our AI will identify the problem with treatments matched to your grass type.
When to treat
Treatment (post-emergent)
Best time: Fall or early spring
Target stage: Actively growing, not flowering
Conditions: Apply when weeds are dry · No rain for 24 hours · Temps 60-80°F
Germination starts around 40°F soil temperature (optimal 55°F). Track your ZIP's live soil temperature or get an exact plan from the herbicide timing calculator.
Control plan
- 1Apply post-emergent in fall when dandelions are actively growing
- 2Use selective herbicides safe for your grass type
- 3Remove seed heads before they mature
- 4Improve lawn density to prevent establishment
Good to know
- • Deep taproot makes mechanical removal difficult
- • Produces seeds that spread easily
- • Most effective control is post-emergent in fall
- • Can be controlled with selective herbicides
Products that work on dandelions
These picks are not filtered to your lawn. Some herbicides damage certain grasses (atrazine is for warm-season lawns; Trimec harms St. Augustine). Verify your grass type on the product label before applying, or use the herbicide timing calculator for grass-filtered recommendations. As an Amazon Associate we earn from qualifying purchases.
curative
Trimec Classic
Classic three-way broadleaf herbicide for tolerant lawns when you need dependable control of clover, dandelion, plantain, and chickweed.
A three-way broadleaf herbicide clears active dandelions on tolerant lawns.
Check price on Amazon
curative
Southern Ag 006130 Atrazine St. Augustine Weed Killer 32oz Specialty Herbicide
Southern-grass herbicide option for St. Augustine and centipede lawns where three-way broadleaf products are unsafe.
For: St. Augustinegrass, Centipede, Zoysiagrass
Southern option for St. Augustine and centipede lawns that cannot take Trimec.
Check price on Amazon
recovery
The Andersons PGF Complete 16-4-8
Balanced slow-release fertilizer for established lawns that need steady feeding without a quick flush of top growth.
Thicker turf is the durable dandelion prevention layer.
Check price on Amazon
Where it's most common
Frequently asked questions
When is the best time to treat dandelions?
Fall, from September through the first hard freeze, gives the best root kill: the plant is moving carbohydrates into its taproot, so a selective broadleaf herbicide rides down with them. Spring treatment on actively growing plants can still work, but expect regrowth from the root more often and plan a follow-up application.
Does hand-pulling dandelions work?
Only if you extract most of the taproot, which is easiest with a dandelion fork after rain. Any root fragment over an inch typically regrows. For dozens of plants a selective herbicide is more practical.
Are dandelions bad for a lawn?
A few are cosmetic and pollinators do visit them. But each seed head makes up to 200 seeds, so a light infestation becomes a heavy one within two seasons if the lawn is thin.
Not sure what's in your lawn?
Upload a photo and our AI identifies the weed, disease, or pest with severity and treatments matched to your grass and ZIP.
Diagnose my lawn free