I found some that only get 30 - 36 " from Easy to Grow bulbs. Some staking could help. Very tempted as Watsonia are so beautiful. Of course you can always plant in ground, dig, store, repeat.
Yeah - Glabs suck in pots. Tried twice and will never try again. Though I do pot up the very small offsets to give them a chance to grow where I can keep track of them. I just keep em in an out of the way place and feed and water. I do this with many "bulbs".