AsNoriuanswered grow question 6 months ago hope you are trolling, otherwise i dont get it. looking at some your current or ex grows, you already know how canna plant grows ...
here its support, not LST. btw done wrong, indoors in controlled environment you can use metal as cage or so for keeping / manipulating plant, but outdoors it will attract more cold during nights, plant can suffer.
add a bit more soil, make weak stem part next to ground part of the root, plant will love it . and i think most important - stop overwatering, medium looks too wet ....
soil needs wet/dry cycle, otherwise roots wont develop, ph swings in pot and nute lockout or even some rot will start...