Liatris Spicata

Liatris Spicata (Blazing Start, Gayfeather). I read that you can propagate this by division. But what is there to divide. Mine were purchased as small bulbs, and have now grown to large bulbs, with as many as 10 seperate shoots from one bulb. Surely you do not cut the bulb in half, and as yet it does not seen to have produced offset bulbs. So how does it expand sideways.

I am also confused by this comment, which I have seen on a couple of sites :- "Plant in sun and moist, well-drained soil. Would suit a bog garden". How do you make a well drained bog garden. :confused:

 

Line it with polythene with holes in it !! :D