let’s put it in perspective. if I were the tenant I would find the cheapest repair guy regardless of quality…. better yet, I would stop watering altogether. depending on how much my deposit was, that might make it worth while. you the landlord deal with all the dead landscape after I move out…..might be cheaper than me paying to fix sprinker + taking care of your landscape + spending money watering….

You still think you should leave this repair ( which should be relatively inexpensive) up to the tenant?

put another way. if a pipe inside the house leaks, would you insist he find a plumber and have him pay for it? what if he decides to ignore it, after all, it’s not his house.