I follow my geraniums with winter-flowering pansies. When you say that you have been growing petunias are they the ordinary varieties or the trailing ones. The Surfinia varieties will in fact produce a second flowering if cut back hard and fed.

If you use winter flowering pansies make sure they have started flowering. They will continue to flower over the winter. Primulas are good as are dwarf wallflower.

Thanks, Jimmytheone, they are the ordinary Petunias.

Also thanks to Scotsgran.