Hi! Glad that you like the game!
The dark garden is divided in three parts, you enter in the middle one and first you have to go to the left part where there is a garden shed with the crowbar. Then you have to go to the rightmost part where the chapel is and use the crowbar to open the door.
The middle part is the actual maze, as a hint, the purple plants/bushes indicate the path to the left part and the red ones the path to the right part.
I hope this helps and that you will continue enjoying the game!