A nice game, I enjoyed playing! Kudos on making all your own assets for your first jam! If I had any suggestions for improvements, I'd say it was a little hard to understand the effects of some of the plants – it seemed like some hurt some enemies more than others, but I wasn't quite sure of the rules. I also ran out of seeds once or twice. I know some TD games let you 'sell' old things you put down to get back some amount of currency.
Good job!