I should know better, but I am still occasionally seduced by handsome plants on the garden centre bench nodding their flowers at me or rippling their shapely leaves. Home we go together, flushed with giddy excitement, and all is rosy for a week or two - or even an entire season. But then, oh, how often things go sour. The flowers fade, mildew sets in, slugs and snails have their wicked way, or the plant sulks and goes yellow. Sometimes, having spent its blooms, it refuses to settle in with its companions and sits there all awkward and incongruous, like an unsuitable holiday beau. I'm sure you recognise the scenario.
Before romping home with any plant, we should ask it: "What will you contribute to my garden when you are not flowering?" So advises Nigel Colborn in Great Planting Plans, a nicely illustrated book that manages to be sensible and inspiring. It appeared in hardback under the title of Garden Magic some time ago, but it has recently been released in large-format paperback for a very reasonable £10.99 sterling.
Mr Colborn is a pleasure to read: he is deeply knowledgeable, and generous with his information, telling us the best and cheapest way to achieve a beautiful garden. The book examines all the choices to be made about plants and their character, and points out some of the common pitfalls (positioning discordant variegated plants together is just one I've fallen into). He discusses plant form, flower shape and colour, foliage type and texture, and the tricky matter of creating agreeable associations. He stresses the important, but often forgotten, additional benefits of fragrance, autumn colour, winter outline and the quality of young leaves. How I wish I had read this volume before embarking on some of the more disastrous ventures in my own patch.
To ensure complete success (or as near to success as we can hope for, given the vagaries of climate and gardener, and the predations of pests) he spells out detailed "planting recipes" for 20 different situations, including "a shady urban oasis", "variations on a potager", "a woodland scene" and "a romantic country retreat". Each recipe, he suggests, can be followed to the letter, or may be used as a rough template onto which we can impose our own ideas. Colborn lays down three simple rules as a foundation for creative planting. One: plants must suit the environment. Two: the gardener must be happy with the plants. Three: plants must be combined to achieve the most pleasing associations of colour, shape, texture, outline and character.
Three simple rules, yes, but not so simple to put into practice. The problem with us gardeners is that, like wild animals, we are creatures of terrible impulse. We need to be trained. Before reaching out to grab a plant from a shelf or a packet of seed from a stand, we need to stop and consider what we are going to do with our proud purchase when we get home. There's no point in carrying off a flamboyant, bloodred, tuberous begonia only to find that it sticks out like a bruised thumb in our airy, pastelcoloured border.
If you must acquire mad-looking, off-key plants (and, yes, being gardeners, we must), the best thing is to grow them in large pots in their own private space - by the front door, on the steps or grouped with other similar whimsies on the patio. As Colborn points out, it is more difficult to harmonise the colours of large flowers than small ones: a bed of clashing dahlias will set the teeth on edge, while a meadow-like spread of scarlet poppies, yellow daisies, pink ragged robin and purple knapweed brings joy to the eye.
Foliage, as well as flowers, must be carefully studied. Some of the loveliest combinations are when broad and delicate leaves are placed together, as in the classic pairing of hostas with ferns. Coloured foliage needs just as much care as variegated: too many non-green plants in one space can look as if someone in last night's fancy-dress outfit has settled down for a little rest in the flower bed.
Looking around my own garden, and with my eyes opened by Mr Colborn's words, I can now see many glaring errors that I'm eager to correct. With late-spring easing into summer, it is a comfort that plants can be moved immediately to more visually congenial locations. And next time I visit a garden centre or nursery, each prospective purchase will be subjected to a rigorous questionnaire. If the plant I'm interviewing can't convince me of its enduring worth, I'll thank it nicely, and move right on. Perhaps.
Great Planting Plans by Nigel Colborn is published in paperback by Quadrille (£10.99 in UK)