lol this is quite a simple problem to fix and heres how you do it:
first off you need to know about layers, The first layer is where your hero walks around and such so put your grass here, for the secound layer you put stuff such as the clock thing you have in your screenshot, for the third level you put things such as teacups on table or chimmneys on the roof of a house and finally the event layer is for all your events such as NPC's. so to fix your proble put all the grass on the first layer and your clock on the secound layer.