There has been many different ways of growing cactus mentioned here on TFO, Well here is another one that I tried and was surprised at the results.I found a pad (in the laundry room) that was misplaced during this past winter, it was good and dry and I had cut some of the top of the pad off to feed the tortoises,I was using the coke bottle system to start some vegetable seeds for the garden at the time,so I stuck the pad in a bottle and filled it with soil and it has been wet since, and is growing faster than I expected.I believe that if kept warm, moisture doesn't bother the winter hardy opuntia,Just like keeping hatchlings moist they must be kept warm.This pad has been sitting in a southeast facing window for about a month in constant moist soil. I took it outside to take the pic. I cut extra pads off my plants in the fall before they go dormant and the ones I don't feed off I usually stick in the ground in the spring to start new plants,but I have so many plants I am giving them away this year again.I wish every tortoise keeper had the same problem.This pad is from one of my newer plants that doesn't get the long spines and is cold weather hardy.-- Hope this helps anyone that wants to grow your own--Len