I like the concept of this one, love the pizza tower inspired art style, nice menu and that walking back and forth animation is great.
It's necessary to read the description to fully get how to play (at first I thought "ghost mode" was the game not working, not intentional): only a certain amount of moisture will make the proper tiles to grow plants, so while invisible, you have to put holes in the available space to prepare the soil with "X", then by pressing "C" you initiate the second phase of the game by dropping the character in, wich with "Z" plants and jumps with "Space".
I'd make some keys do multiple things ("X" for both putting holes and planting or "Space" for changing mode and jumping), get some funky music and more sfx somewhere to put in (Assets are allowed, don't be stubborn! One week is a very limited amount of time), some UI and in general make things clearer in-game ("Ghost Mode" text on top, which tile is the right one) and that's about it, the game loop is addictive. As a jam entry, it'd be incredibly solid already and, with more layouts and plants, this would be one of the tops I feel!