Cutting height is based on the kind of grass in the lawn.

And the frequency of mowing can be somewhat controlled by the fertilization routine. And the time of year really dictates rate of growth.

But remember, cutting needs to be done on a regular basis no matter how high you set the blades. Once a week is a good routine, if you can talk your clients into it. Twice a month and you'll be taking off too much at any one cute, no matter how high the grass is. That is very stressful for the plant. That's a tough sell to the typical lawn service client.

There is a direct corrolation between the length of the blade and the growth of the roots. Healthier, deeper, and stronger root systems means healthier grass requiring less water and fertilizer.

I'd encourage you to try to sell annual contracts where the customers pay an AVERAGE fee every month, whether you show up once a week or once a month, or as needed.