Why is a birch-tree like a melon?

This is the time of year for armchair gardening. The cold, dark days give one the chance to ignore the muddy plot outside and to sit by the fire with a heap of catalogues. As one reads the thrilling descriptions, next summer’s garden comes to life in the mind’s eye. There are no rabbits, mice, moles, whitefly or weeds to spoil the picture. Instead, the most difficult plants flourish under a sunny sky.

These two mighty tomes add up to the most inspiring catalogue I have ever read even though, unlike commercial lists, the descriptions do not exaggerate. They are strictly truthful, because they are written by Dr Martyn Rix, a distinguished botanist. The illustrations are by Roger Phillips, a painter turned photographer who uses his camera with the eye of a true artist. Rix and Phillips have been working together for 25 years and have produced 23 books, including 14 in the brilliant, best-selling Garden Plant Series.