Bruce
Herd Master
I have a rhubarb plant, came with the house so I have no idea how old it is but it was "full grown" when we bought the place 9 years ago. The stalks are good size but unfortunately it is more of a green than red variety. The rhubarb sauce isn't as pretty as what my grandmother in So. Cal made. I would guess that like asparagus, once the stalks are starting to get reasonable size you can take a few without damaging the plant.