This year's crop: The best gardening books of 2008

A village fête is a delicate indicator of the worth of any new gardening book. If after two hours on the bring-and-buy stall, a review copy at knockdown price still has not shifted, you can safely suppose the book is a bummer. Sometimes the titles are a giveaway. Sixty Ways with Begonias or Threnody in a Cottage Plot are surely bound straight for the remaindered shelves.

For myself, it's the books that never get on to my shelves that are the winners: the ones that stack in piles on the floor by my desk or teeter on bedside tables because there is always something in them that you want to ogle or look up. But I've become rather ruthless in sorting new gardening books. So often, the new is only a rehash of something you've already got. In that case, you need to ask yourself whether it is better. Is there an interesting new angle? Is it better written?

With basic reference books, what you need is the latest edition, which is why I'm putting the new A-Z Encyclopaedia of Garden Plants (Dorling Kindersley, £55) at the top of my Christmas list this year. Five years have passed since the last edition of this two-volume encyclopaedia and we are now even more obsessed with grasses and herbaceous perennials than we were in 2003. The shifts are small (none of the new alliums such as 'Ambassador', 'Mars' or 'Mount Everest' make an appearance) but the encyclopaedia has always been stronger on species than varieties, as species do not come in and out of favour so speedily. But nevertheless it is surprising to see, for instance, that the hippeastrum entry is still so limited and still includes old, superseded varieties such as 'Liberty' and 'Orange Sovereign' that do not even appear in The Plant Finder. There is hippeastrum life beyond old stalwarts such as 'Apple Blossom' and 'Red Lion'. The real treats in this family are the orchid-like hippeastrums such as Hippeastrum papilio and 'Emerald' with narrow petals weirdly striped in pink and green and cream. These are hugely popular, easy to grow and widely available. Their arrival each autumn in ever larger numbers is one of the shifts in gardening taste you might expect to see reflected in this new edition.

Paradoxically, I seem to have ended up with more criticism than praise of this encyclopaedia, which is unfair. It just reflects how familiar its pages are to me. All gardeners need a well-illustrated, dependable plant book to refer to and this is the best there is. You won't spend a better £55 this Christmas.

Tim Richardson is a rare writer and he tackles subjects that I know too little about, so his books always stay on my shelves. To me he is the best possible interpreter of people who obviously find difficulty in interpreting themselves. Take the New York conceptualist designer Ken Smith who says his landscape work involves "multiple constituencies and complex contextual situations" as well as "specificity of content and abstraction of interpretation and meaning". Wherever they are from – the States, Germany, Japan, Sweden – all the designers in Richardson's new book seem to talk like that. Groping for what they are trying to say is like trying to grasp an idea floating past you in an underground water tank.

So this book, Avant Gardeners (Thames and Hudson, £24.95), is essential reading for people who like Wallpaper* magazine and who remember with regret the too-short life of Richardson's own eclectic magazine New Eden. In Avant Gardeners, he says, he is presenting "the 50 most exciting and innovative contemporary garden and landscape design practices from around the world". Seven of his own essays are dropped at intervals through the book and illustrate how "a rising generation has rejected the naturalistic tradition of Western garden design, favouring instead the influences of Modernism, Post-Modernism, Pop Art and Land Art". A generation, then, who seem to resent the cash and fame that have come Damien Hirst's way, and who are intent on packaging their work in a way that has more to do with art than craft.

But a designer who understood craft a little better would have made a more successful job of the notorious Princess of Wales memorial fountain in Hyde Park. If designers were less arrogant, perhaps they would listen more carefully to the meaning of their own quotes: "Designers: ask not what you can do for a landscape, ask what the landscape can do for you." Yes. Absolutely right.

These conceptual spaces, though, are notoriously difficult to interpret from images. We don't have that problem with spaces organised in a more traditional way. In our minds, we can supply what happens when the photograph bleeds off the page. But this is the most important book of the year for me, thoughtful (Richardson always is), beautifully produced and taking its readers into much unfamiliar territory.

With William Robinson: The Wild Gardener by Richard Bisgrove (Frances Lincoln, £30) we are back on known ground. Robinson, the opinionated Irishman who made a spectacular garden round his house at Gravetye Manor in East Sussex, is one of the best known figures of the Edwardian gardening scene. Wild gardening was very much his style and this book is a timely reminder that there is more to it than dumping superannuated clumps of Shasta daisy in a spare patch of ground.

Bisgrove, director of the landscape course at Reading University and a long serving member of the National Trust's gardens panel, has already written a magnificent book on the gardens of that other monumental figure of the Edwardian age, Gertrude Jekyll. One of the most interesting facets of his present book is the picture he draws of the relationship between the two of them. Jekyll wrote for Robinson's magazine The Garden and Robinson was a frequent visitor at Jekyll's Surrey garden, Munstead Wood. Bisgrove includes an enchanting sketch made by Jekyll of the bulbs she had bagged up for Robinson to naturalise at Gravetye: trilliums, sanguinaria, grape hyacinths and a white anemone called 'The Bride'. The book is generously illustrated, but it's not just for ogling. It demands to be read.

My final Christmas book, Close (Northfield Print, £19.99), is by a young photographer, Allan Pollock Morris, and documents work by contemporary landscapers and gardeners that he came across on a journey from south to north through his native Scotland. Andy Goldsworthy is there of course with his superbly enigmatic cairns, but so are lesser known figures: labyrinth-maker Jim Buchanan, letter-boxer Alec Finlay, Rolf Roscher and Chris Rankin's hidden miniature landscapes in Glasgow. Though I go there every year, I'm an interloper in Scotland, but this beautifully made book made me feel as homesick as if it were my own country too.