Posted: 04/05/2013 at 21:28
I grow mine in pots . I have 2 large glazed pots, each with 7 plants. They stay out all winter with a bin liner over them as the only protection. They have survived now for many (7/8?) years, and in the summer each pot has about 50 flowers. They must be really congested by now but so far, fingers crossed there is no sign of problems or reduced flowering.The varieties with the thinnest leaves are the hardiest, so my wider leaved (white) ones are given more protection in the winter by moving into the greenhouse. They seed around into the gravel drive they sit on and it is easy to prise them up and pot them on. They have strong roots and get away easily.
Grow them in nice pots for this year, see how you get on with them and then decide what you want to do with them for the future. You may decide to stick with the pot option. Enjoy.