Do you pinch them out?
I treat them exactly the same as dahlia's from cuttings then they make nice bushy plants. I do mine when they have made 4 or 5 pairs of leaves.
Even if you dont pinch them they are still inclined to side shoot and become bushy
Thanks!
I succumbed today to buying some tubers having lost mine last year in the winter. I kept trying to resist so ended up too late for seeds and had to buy tubers ???
Sorry I posted my enquiry before I saw this post. So I can pinch them out.