It takes about 4 days from the baby mushrooms first appearing, to be ready for harvest.
When they look ready PICK! Simply pluck or use a sharp knife …else you might end up with a spore storm. If they do spore, the mushrooms are still good to eat.
Sometimes it’s difficult to predict when to harvest. With the greys, you will notice the caps starting to turn up at the edges, thats a good sign they are close to ready. Best way to tell is to observe them, and apply learnings to subsequent flushes.
You should get 3 flushes (aka harvests) over a period of about 6 t0 8 weeks, if you care for it.
If it stalls on number 2 or you really want to try extending the life soak it in a bucket of water overnight. We have had some customers get more than 6 harvests over a period of 5 months.