Yes, seed is the best way and quite successful. Sow them in a warm greenhouse in a pot or tray of fresh seed compost ( cover with about quarter inch of compost and press down gently)and water carefully. Put the pot in a polythene bag to keep it damp. They should germinate in a couple of weeks and then pot them on as needed. Beware of growing 2 pots too close to each other as they quickly twine together and are hard to unwind!! Put sticks into the pots for them to grow up. They can be kept in the pots or planted out in a sunny sheltered place in late May. They aren't winter hardy in UK so either dig them up in autumn or collect seed and keep for the following year.

Thankyou Volunteer for your help. I look forward to a summer full of Purple Bells.