I love the idea! I saw that you plan to add more types of pests and counters for them, which I think you can have a solid releasable game even if you only add even 1-2 more varieties of pests and powerups.
I was a little confused when I saw that the trees were flowers, but I figure those are placeholders. I wondered if there was an optimal way to place the plants and thought it was a little odd that I could uproot them so easily and move them elsewhere. I think it would be more engaging and challenging if you couldn't move your plants after you placed them since this will allow for the player to be more strategic in how they want to plant their garden and not lose all their plants to pests.
Keep up the good work!