I think once you reach grandmaster at gardening you should be able to hire a gardener to keep all your plants alive and pest free. I maxed out my gardening levels and simply never harvest cause I want a garden but don't want to take care of it and without being able to level anymore in it gardening ceases to be worth it for me. I would like to hire a gardener for a week at a time and simply have a nice garden to look at when I port home.
Hmm...If KI did add this it would probably be for Crowns. I think it would be a nice idea if you could do it for say a thousand a day? That seems reasonable... Plus if you go on vacation you could hire one!