I think you have a really solid concept, and it's clear what you're trying to accomplish with the game. The mechanics you've shown so far seem like a good fit for the idea, and your production plan feels realistic and well thought out for the game jam.
One thing I really liked is that the game teaches players about something most people probably don't know much about. I actually had to look up what grafting was so I could fully understand the concept, which made me appreciate the educational side of the game even more.