Does tenant have right to make decision on this?

You just can't make people care about the same things you care about. It's a lot of work to maintain a lawn & you have to be interested in that to make it worth your time. They don't own the property & gardening probably isn't their thing. You really can't water whatever you want & whenever you want & expect someone else to pay for your interest. You can't control what they do or don't care about.