The quote says it all. People need to go in to bamboo with both eyes wide open and be prepared. After all, we all know about 'dwarf' conifers that will revert in time. 'Clumping' is a question of time. Time, ground conditions and climate.

I grow 20 varieties and I reckon bamboo takes four years just to settle in. If it likes its situation by year seven its moving like a train! But it IS beautiful!

I've come across many garden visitors who have planted bamboo and then been forced to go to considerable effort to remove it. I believe many households are in for a shock in years to come. Just as householders here in the UK have, for the past 35years, been advised that there was really only one plant to grow along their garden perimeter (Leyland cypress). Yet only fairly recently is the Govt legislating against it. And Leylandii remain where they are planted . . . .