Plants outside a window can never grow through the window into the house because they always grow towards the light. You would need a permanent light source inside the room that outshines the sun during the day to achieve that.
Ticks do not drop off when you hold a lit match to them, leeches do.
In the previous episode Earl offered to return the stolen blue door on his car to its original owner, but in this episode he still has the blue door on his car.