I have only tried a parm a couple of times. The first I waxed and for the life of me, I couldn't stop the mould growing. For the second one, Wayne advised to rub with oil, then in two weeks rub with salt, then two weeks later rub with oil, and keep alternating. The cheese is only about 6x2.5 and is almost 1 year old. I oiled and salted every fortnight for about 4 mths, then found I could drop back to once every month. Absolutely no mold. So fingers crossed that when I open this in another couple of months it will be good.