I mow maybe 5 yards, and next year it will be down to 3. The only reason I mow these accounts anyways is that they are full maintenance clients and they requested the mowing.
I can't compete mowing only because I can't just mow and go and call it good. I'm always picking up sticks, weeding, edging, sniping a few shrubs, etc... Ultimately my price is higher than other mow services and I tell any potential client that.
I primarily do landscaping and that is 90% of my business. My business model has done well for me, but the only drawback is the not-so steady income. I've had some banner months, and some extremely slow months.
My only other problem with my set-up is that the economy, and my smaller market is pushing down prices for services. Not only is every Tom Dick and Harry out mowing, but now they want to landscape. Where I shine is that I have the knowledge to do it right and I've fixed my fair share of installs. That and I also get business because the mow guys just want to mow. I've acquired a few accounts just because of that reason, and I have a feeling that as time progresses, that is what the mowing industry will have to adjust to, which is full service.
It can work, but you just need to make sure you are marketing yourself correctly and getting the landscaping business. To compensate for the income stream, I have a good amount of landscape maintenance clients where I go in once every 3 weeks and take care of everything but the mowing. That helps fill in between the landscaping and hardscaping installs.