An absolutely fantastic concept, extremely creative and excellent art direction. However, I think it would have been smart to focus on bugfixing and tutorials over the - admittedly excellent - polish that's in place. Without any means to fight back until your first plant grows (which can take a fair while), it's impossible to figure out the core game loop and get invested. Also, the bug of dying not actually resetting the plant growth state and making you immortal really hinders gameplay.
That said, this is still solid work for the timeframe and if you iterate on it a little more I think it could easily be the best game to come out of the jam! I could see myself come back to this game well after the jam's over if it's gone through a feedback and bugfixing cycle or two.