Reset a sprinkler timer - should that be tenant's responsibility?

[Nate Waters]

Hello all!

Background: I live in Orange County, CA and I just purchased 2 SFRs in Colorado. This is my first attempt at remote investing. Both homes are new construction and I am attempting to manage the properties myself. I know, I know...I'm asking for trouble, but, here is my logic: The houses are under a full warranty for the first year, so, if I need any repairs done, they will cover it. After the first year, I plan to see how it goes then decide whether or not to hire a property manager. I also have a couple friends in the area that could help me out if need be - but I would rather not ask them for favors if I can help it.

The first crack in my logic: One of my tenants let me know that the sprinklers turn on 3 times a day and the grass is very soggy. I asked if they would mind dialing back the sprinkler timer and they responded that they are not comfortable setting the timer, will not do it, and want me to take care of it. 

Now, I AM the landlord...I get it...but per the lease contract, they are responsible for maintaining the landscaping in a manner consistent with the neighborhood (keep the grass green and cut). In your opinion, is this my responsibility or theirs? If the rental was around the corner I would take care of it and be done with it.

Thanks in advance for sharing your opinions and experience!