using mushroom bags

I have a couple of mushroom patches with a mushroom bag tightly wrapped around each patch. I was wondering if you need to cut small holes or slits in mushroom bags in order to allow mushrooms to grow through the bag or will the mushrooms push through the bag on their own? To me, it doesn't seem as if they could push through the bag on their own. Thanks

you will need to either poke holes or make slits for the fruits to come out of the bags.