The five petals are fused together into a bell shape at the base, like its relatives, the campanulas.
en.wikipedia.org Glossy yellow trollius hovered above fragrant orchids, clovers, campanulas, hardy geraniums, oxeye daisies, viper's bugloss, ajugas, scabious, thyme, thistles, hyssop, salvias and dianthus (to name but a few).
www.telegraph.co.uk Among perennials, good companions that complement their colouring include border phlox, penstemons and monardas or plants that produce a soft contrast in colour and form, such as campanulas or veronicas.
www.telegraph.co.uk The winners are the many campanulas, at their best this weekend.
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