And when harvesting the cacti, try and only cut the head off without causing damage to the root, this will result in the cacti sprouting multiple heads and carryin on growth, so within a year or so, you will be lookin at a freaky multi headed cactus, that will once again be ready to harvest, as opposed to destroyin the whole thing and waitin over 15 yrs for another seed grown cactus to reach maturity. I got a few multi heads in my window from when I harvested my first batch a year ago, they're growin nicely and should be ready within the next year.