You should hold off on mowing a new seeding until the turf is approximately 5 to 6 inches, at which point you should mow off about ⅓ of the height. If a lower height is desired, allow the grass to regrow for a while and mow to the desired height, never removing more than ⅓ of the height of the turf. A new seeding should be mowed with a push-mower if one is available; if a riding mower must be used, do not mow if the ground is soft enough to result in depressions from tire tracks.
For sodded establishments, begin mowing after rooting has taken place (you can determine this be gently tugging at the sod). As with a seeded turf, do not mow more than ⅓ of the height in a single mowing.
One of the most common errors homeowners make when mowing fine fescues is mowing them when it is too hot and/or dry--it is very important to not mow under dry, hot conditions as this will severely damage the fine fescue turf.
Finally, be sure to always return clippings using the mulching option on your mower because they provide valuable nutrients to the lawn. However, if clippings form clumps that cover the existing lawn, bagging would be better in this case to avoid smothering the establishing grasses. Watch the video below for more mowing tips.
Next lesson: Watering a roadside lawn