Both an excellent puzzle game, and a very well polished one! Especially considering you tried to make it a restricted time limit.
It was a very interesting challenge with just a few set restrictions, but many possibilities to consider. It took a while figure out certain "patterns" and tricks to look for to maximize charm though, and I felt a little like the levels where you are let to openly place (in larger more free form areas) came a bit too soon. I would have preferred a few more smaller levels to get used to placement organization, and I got majorly stuck on level 17. I also got a little stuck on 19, but got through that, then somehow 20 was easy (maybe because there were so many preplaced elements?)
Small note, but sometimes I found that the tiles wouldn't switch even though I clicked on them and they appeared highighted. But I realize you made this game quickly so it's no big deal.
I really thought this was a great puzzle and gardening themed game, very well done! I'm no designer, but I think there were lots of small details that made things look nice and play well, and also small things like a different "continue" dialogue from Mr Tulip was a nice touch!
I look forward to seeing more games from you, keep up the good work!