I was wrong about M. Basjoo not producing sword suckers. Yesterday, I found sword suckers on a M. Bajoo in Proksa Park, Berwyn, Illinois:
But, I submit that the water sucker on my M. Basjoo is the result of my plant being either genetically or epigentically defective rather than growth practice. Most likely, I was sold a genetically defective runt out of a group of seedlings. This is the second M. Basjoo plant that I purchased and the first was a more vigorous grower. The first survived three years outdoors (zone 5). Sorry, I don't remember where I purchased the plants. I remember that one seller was Stokes Tropicals but I don't remember whether I bought the first or second Basjoo from them.
Regarding the possibility that my present plant is epigeneticaly defective, my present plant is a water sucker of a water sucker of a water sucker of a water sucker ....