When I got my last gardening laff point, I just continued to casually garden after that. Meaning, I eventually completely maxed, but I did so just recently (gardening came out, well I don't remember exactly lol). Point is, after I got the last laff point, I gardened here and there, because I hate gardening and there is no reason to make it to the end right now. But as others have said, you never exactly know if they are going to add more flowers and trophies, so that is the reason I finished at all. If you hate gardening like me, garden two or three times a week, or even once a week. This way, you don't have to worry about another full month of everyday gardening, and you now have the ability to garden at your leisure so that you can eventually make it to the end.
Just my advice