Calamagrostis - Calamagrostis - Some useful ornamental perennial grasses in this group - especially for slightly damp areas.
Camassia - Camassia - Gorgeously dainty erect stems of white or blue flowers on this late flowering group of bulbs. Well suited to a semi shaded spot in the perennial border.
Cardiocrinum - Cardiocrinum - This bulbous perennial will have beautiful trumpet bell shaped blooms nodding away over the lower perennials.
Carex - Carex - Somewhere in your garden you can find a situation where one of the wide range of grasses will flourish. Many are good for all year interest, and a brightly coloured golden evergreen amongst them.
Convallaria - Lily of the Valley - Whilst the common white flowered Lily of the Valley is popular, there are several others - including pink flowered, and variegated foliage types - available.
Cortaderia - Pampas
Corydalis - Tuberous Corydalis
Calamintha - Related to - and resembling - the mint family. Wide range of uses including rockeries, borders and semi woodland areas.
Calceolaria - Slipper flowers - beloved of florists. But there are a few perennials that are quite hardy and rather different to the gaudy pot plant relatives. Calceolaria acutifolia being a good choice, and doing well in most winters.
Calendula - Not really true perennials, but tend to re-seed themselves so that they are always there! Early splash of gold or orange colours.
Caltha - An ideal buttercup-flowered perennial for a bog garden or any swampy area.
Campanula - A wide ranging group of many varieties and types. It will fill a few pages once I get round to it.
Cardamine - Bittercress or sometimes known as Dentaria. Wise ranging group of hardy perennials can be found a spot in nay garden - and almost any situation if you choose the right one. Pink, Pinky-blues and white are the main colours.
Carthamus - Thistles basically - but not invasive as are the wild ones. Yellow flowers atop varied foliage.
Caryopteris - Caryopteris is of course a shrub - or maybe sub-shrub. Much depends upon where you live. In colder areas it will grow better as a herbaceous perennial - springing forth each spring. It would certainly be a welcome addition to most borders for its late blue flowers.
Catananche - Very similar to, and often mistaken as - Cornflowers - Centaura. Cupid's Dart is the common name. One of the best of the blues is a short-lived perennial, but well worth the time it spends with you.
Cautleya - Unusual perennial with spear shaped leaves, and red and yellow flowers and bracts. Good for a shaded and sheltered area of the border.
Celmisia - The New Zealand Daisy - generally with silver foliage - according to choice of variety.
Centaurea - Knapweeds, with colour and sizes for choice. Mainly hardy with evergreen foliage. Almost all are clump forming.
Centranthus - Valerian for a dry wall, bank or any other inhospitable place. If you want beneficial flying insects - such as bees - then this has to be the choice if you have the right site.
Cephalaria - Interesting few perennials that have flowers similar to the Scabious - but yellow. Can get to around 2m high, and a bit straggly. Interesting.
Cerastium - Snow on the Mountain is the one we will detail. Silver foliage awash with pure white flowers in late spring.
Ceratostigma - The shrub forms are normally grown, but there is an interesting spreading perennial in Ceratostigma pumbaginoides.
Chaenorhinum - Dwarf Snapdragon. Really dwarf and ground hugging, but with typical pinking miniature snapdragon flower spikes.
Chaerophyllum - Chervils. Edible roots on some. Ferny foliage and assorted colours but based upon pink and white.
Chamaemelum - Chamomile - For a lawn, you need Chamaemelum nobile - also known as Anthemis nobilis.
Chasmanthe - Cormous perennial not unlike the Crocosmia - but different.
Chasmanthium - An interesting ornamental grass with un-grassy flowerheads - that of time look dead. Dappled shade is goof for thi worth-growing perennial grass.
Cheilanthes - The Lip Ferns absolutely thrive in the dry. Stone walls and the like. Evergreen perennial ferns that like the sun. Now that's different!
Coniogramme - Fern
Consolida - Larkspur
Convulvulus - Bindweed
Coreopsis - Tickseed
Craspedia - Bachelor's Buttons
Crepis - Hawk's Beard
Cypripedium - Lady's Slipper Orchid
Cystopteris - Bladder Fern