i never gone into the back garden of the church i go to see if it is open every 2 days or so

You have to befriend Carter, the priest at the Church. He likes wine. Give him wine every day for a while, then you will get a small scene with Zack and Carter. Go back the day after the scene occurs, and you will be able to get into the back garden of the Church, or Carter's Mushroom Garden. you will be able to pick mushrooms and truffles there in the Fall, and White Grass in the Winter.

I hope this helps you out.

cheers, emmie

Actually, there are two ways to get behind the church:

1) Give Carter daily gifts of things like wine and bread, and soon enough, (at least, this is what happened to me) in about a season (if you give him gifts every other day) the door will just open without seeing any events. I'm not sure if that is supposed to happen, but that is what happened to me.

2) There is an event that happens inside the church after
6:00 PM I believe, (Emily, I think you got two different events mixed up!) where you walk into the church and your character looks around for Carter, surprised that he is not there. He walks up through the door in a cutscene and spots Carter crouched by a truffle. He is surprised to see you have found his secret area (you can find truffles and shrooms in there) so he tells you that from now on, he will leave the door open all day long for you to collect his prizes.

Hope that helps. Emily, you were thinking of an extra scene where Zack delivers a mysterious package to Carter that he seems overjoyed about... that is not the triggering event though.