How high should you mow an Ottawa lawn?

Why taller grass often performs better

More leaf surface supports photosynthesis and can shade the soil, helping retain moisture and limiting some weed germination. Taller turf also supports a deeper root system when the other growing conditions are suitable.

Use the one-third rule

If the lawn becomes overgrown, do not force it back to the target height in one pass. Remove no more than about one-third of the blade, allow it to recover, then mow again.

Adjust for Ottawa weather

Raise the mower during hot or dry stretches and avoid mowing when turf is saturated. In spring, frequency may increase because growth is faster. The calendar matters less than the actual grass.

Match the mower to the target

Confirm deck height on a hard surface rather than trusting the lever number, which may not equal cutting height. A sharp blade makes a clean cut; ragged pale tips after mowing usually signal that the blade needs attention.

Alternate mowing direction where practical to reduce repeated wheel tracks and avoid scalping uneven ground.

Clippings usually belong on the lawn

Short, dry clippings break down and return nutrients. Collect them when growth is too heavy, when leaves would smother the turf or where disease considerations make removal sensible. Clippings do not create thatch in the way many homeowners assume.

The final cut of the season

Continue mowing while grass is actively growing. Avoid leaving it excessively long and matted into winter, but do not scalp it. The correct timing follows growth and weather rather than a fixed calendar date.