The game looks great, especially the title screen! Excellent use of lighting to tell the time of day, and all the art assets fit together nicely with each other.
Some of the core mechanics could definitely use ironing - planting several of the same plant is difficult since you need to re-select your held plant each time, especially when the select icon moves to the right as soon as you hover over it. This could be solved by having the player keep holding onto the plant, or implementing hotkeys for each of the plants.
Additionally the first time you play the game is quite brutal - I spent my first attempt reading up on what all the plants do, and by the time I had planted my first tree it was nighttime.
However, the core gameplay premise is great - a maze-style tower defense game where you yourself are the start point for the enemy wave definitely has some potential. If you made the planting easier, and added some incentive for the player to run around the plants (collecting coins for instance), you'd have a solid gameplay loop.