We can learn much about garden plants from their relatives in the wild: how they grow naturally, where they colonise, and what conditions they choose in order to thrive. "As gardeners, the more we know about the plants under our care, the better we treat them and the better they will repay us. So many of the plants we grow are somebody's wild flowers somewhere," says Carol Klein, whose new book, Wild Flowers: Nature's Own to Garden Grown, looks at our most seductive native flora and what they teach us about their cultivated cousins.
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Take clematis, for example. When you see old man's beard, Clematis vitalba, scrambling through hedges and over banks on an autumn walk, you realise that your favourite garden clematis can be displayed in a more imaginative way than slap bang against a fence or wall. The viticellas are the low-maintenance purple-toned clematis that bloom like crazy in high summer and don't suffer from clematis wilt, so are a great choice for town gardens. Klein suggests growing them through shrubs, up trees, obelisks and arches, as well as in containers. What you also learn from countryside clematis is that although all clematis like their heads in the sunshine, they prefer their feet to be in the shade.
What do you do with the blank space in the middle of the border? The dark and dingy area under the trees where nothing will grow? Plant hardy geraniums that will flower for weeks on end, then give you a second show when you shear them back. Cultivated cousins of the meadow geranium that have now, notes Klein, adapted to pastures new, ie road verges, the cranesbills are classics for weaving a sea of soft colour around shrubs and perennials.
Klein's choice for brightening dark corners from May to November: evergreen Geranium nodosum. Her prize for the most delectable: flashy Geranium psilostemon, with black-centred magenta blooms. And if you want nonstop flowers all summer and autumn from a container that receives no sun, she suggests planting blue Geranium Rozanne among hostas and ferns.
Alliums are amazing, especially when you consider that the spectacular Allium schubertii, with its giant flower head resembling a firework in mid-explosion, is related to the humble wild garlic of British woodlands.
Klein gives this showstopper its head by cramming the bulbs into a huge tub, where they stand like giant pink sparklers, and suggests weaving the cheap-as-chips Allium sphaerocephalon among clump-forming perennials in the border, where they will make ribbons of colour from claret flowers.
Wild flowers have a simple charm and some, such as the woodland bluebell, the scarlet corn poppy and the true sweet violet are perfect, and cannot be improved upon. However, many wild flowers are eclipsed by their showier hybrid offspring that are more suited to the garden. Sweet scabious Scabiosa atropurpurea can be wishy-washy in shade, says Klein, but its cultivar Ace of Spades, with garnet pincushion heads, is the new, improved version.
Yarrow or Achillea millefolium is a pretty enough field flower, but the new cultivars, with their larger, flat flowerheads in luscious shades of golds, oranges and reds, are knockouts and, as Klein points out, thrive on neglect: seek out Terracotta, Marmalade and shorter, lemon Moonshine. Hybrid hellebores, with their many-petalled flowers tinted dark chocolate, are even more stunning, if that is possible, than their beautiful predecessors.
Photographs by Jonathan Buckley