Questions about trees

I am trying to get a perfect town rating. Isabelle keeps telling me the town needs more greenery so I am planting trees and flowers. There are a couple things I would like to get clarification on if anyone knows:

When you plant the tree does it go toward your number of trees when you plant it or does it have to be fully grown?
I don't want to have her tell me more greenery everyday if I just need to wait til the trees are grown.

If you talk to Isabelle more than once in a day will her answer change? This goes back to the 1st question in that if baby trees count and I have enough after planting them and ask her again will she say something else(i.e. more pwps or your town is perfect etc) or will she just say more greenery no matter how much I plant that day?

Thanks

it has to be fully grown and you should aim for 100+ trees

for the perfect town rating, you have to have between 110-200 trees. this includes bamboo too, but doesn't include tree stumps or bamboo stumps

i'm not exactly sure if baby trees count, but i thiiink they do, starting from the day after you plant them.