@FatTribble23 I started a new game over Christmas and it was my first new game since 2017, so the first time I've not had perfect plants in a very long time. I grow a bit with pretty much every household I play, even my Sims who live in San Myshuno apartments always grow a half dozen or so plants in pots.
Anywho...it's a LOT slower than it used to be.
My first household in this game, who live out in Old New Henford ended up getting some golden hens who raised up all of their plants to perfect relatively quickly, but the second household is doing it the old fashioned way and at this point both of the Sims in that household have gotten their gardening up to level 8 just from tending their plants; the highest any of the plants has obtained so far is "Nice".
At this rate it is going to take several generations of Sims before the plants in that house reach perfect.