When I briefly owned a rental I always thought it was up to the tenant to maintain things like the grounds. Just like if you lease a car you don't take it back to the dealer every time it needs a wash. Same goes with a house, it's up to the tenant to mow the lawn and make sure the gardens are tidy.
I don't mind too much on gardens though, as long as the edges and lawns are done I don't mind too much. I would expect the tenant to maybe tidy up the gardens every few months.