For most lawns in Southern Ontario, keep your mower set between 2.5 and 3.5 inches. Taller grass grows deeper roots, handles heat better, and keeps weeds down. The sweet spot is around 3 inches.
Cutting grass too short stresses it out. Taller grass shades the soil, helping it hold moisture and fight off weeds. Itโs a small change that makes a big difference.
Most Southern Ontario lawns use cool-season grasses. Hereโs a quick cheat sheet:
Set your mower deck around 3 inches and youโll be in the safe zone all season long. It balances appearance, durability, and root health.
Cutting high lets your grass thrive, but only if you donโt let it get too long. Stick to the one-third rule: never cut more than 1/3 of the blade at once.