Identify & Eliminate
Every Lawn Weed
in Your Yard

It depends on the weed type. For broadleaf weeds like dandelions, a post-emergent selective herbicide works within 7–14 days — see our dandelion killer guide. For nutsedge, only a sedge-specific herbicide containing halosulfuron will work. For driveways and paths, a non-selective formula gives the fastest visible results.

Yes — iron-based herbicides (FeHEDTA) are selective broadleaf killers that are safe for pets once dry. They work on dandelions and clover without harming grass. See our full pet-safe weed killer guide for tested options and safety drying times by product.

Killex Lawn Weed Killer Concentrate is the most widely used broadleaf herbicide in Canada. It controls dandelion, clover, plantain, chickweed, and 50+ other broadleaf weeds without harming lawn grass. Read our full Killex review and our complete Canada weed killer guide for dilution ratios, timing, and which grass types are compatible.

Yes — a thick healthy lawn is your best long-term defence. Mow at 3–4 inches to shade out seedlings, water deeply but infrequently, and overseed bare patches quickly. For active weed problems, corn gluten meal acts as a natural pre-emergent, and iron-based products kill broadleaf weeds without synthetic chemicals. See our organic weed killer guide for the full breakdown.

Apply pre-emergent when soil temperatures reach 50–55°F (10–13°C). In the southern US this is late February to March. Northern US and southern Canada is mid-April to early May. Northern Canada can be as late as mid-May. Use our fertilizer and timing calculator for your specific lawn type.

Enter your lawn size (in square feet, square metres, or acres), select your grass type, and choose the current season. The calculator instantly shows how much nitrogen and fertilizer you need, how many applications per year, and the best timing. You can also use the full fertilizer calculator for NPK ratios and soil test-based recommendations.