Nice idea! I love tower defense!
Would have been nice to have some tracks that showed where the pumpkin would be coming from, I wasn't sure where to place my scarecrow once the game started. Also, having a different enemy that the scarecrows can't attack could have made the game a little more challenging, something like a crow would have been a good idea :)
P.S: I played your game in my stream today if you want to see my live reaction!