Okay so I seem to be the only one having merging issues lol, which prevents me for going to bigger waves, but fun game nonetheless
Thank you very much for playing ! Did you try to drag & drop 2 of the same plants over the 3rd one? This is a little snippet that might help you:
If it does not work like this, let us know and we will start bug hunting! :D They hurt our plants, lol
Yeah my bad, found out after a while that you had to drag two plants to make it happen! So no bug here haha, congrats for your game!