This is the review I wrote for Amazon. The url to the original is at the foot.

Exotica 4 series is in two large (over 2,000 pages in each) encyclopedic volumes. Series 3 had something like 11,000+ photos of 9,000+ species; Series 4 brings some 16,600 photos of 13,980 species. And oh, the joy, when you find a plant not included. And then the fear - because - now where do you look?

The detail included in Exotica 4 is exquisite - e.g. what is the difference between Pelagoniums and Geraniums? If you don't know AND don't care, then Exotica 4 is not for you. Despite that, Exotica 4 isn't really all about horticultural trivia. Graf recommends referring to specialty literature for the more arcane information about obscure varieties and cultivars. Just so you can dazzle friends and family, Pelagoniums have seven stamens whereas true Geraniums have 10 (page 1171).

It's about the photographs, simply. The photographs are (mostly) in sharp black and white with the plants grouped by families. As in many family portraits, the relations can look quite strange. I found this an advantage when identifying species - I wasn't distracted by colour printing variances - and if I could find a plant that looked like the one I wanted to identify there was a good chance it'd be nearby. I used these books (in association with Tropica - the colour picture, single volume) when I ran a wholesale/retail houseplant business. We often had customers coming in saying, "I have this plant at home - its got green leaves - what is it?" Exotica 4 never missed.

Exotica 4 doesn't try to be one of those coffee table type of gardening books which drip temptingly stylised photos of divine plants, but with limited information or substance. Instead it is aimed at the nursery grower or horticultural enthusiast who knows what a good specimen plant looks like, and now would like to know the name, or where it comes from. I found learning where the plants came from fascinating. The photos of plants in their natural habitats gave further clues about their care and maintenance.

There's good information, in code, about the care of each and every (mind: 13,000+ species) plant mentioned. The code has keys in English, Spanish, German, French and Russian - not a bad attempt to give meaning to "International" - and an illustrated description of botanical terms. Basic information about propagation, pests, lighting and use of plants in the home and offices is included - although if you are keen enough to invest in these books you probably know all about these topics, and again, specialty literature exists.

Many of the houseplants, which remain meek and mild-mannered in your living room, grow into forest giants. I enjoyed Graf's inclusion of photos of mature specimens - no wonder the fruit salad plant is called Monstera deliciosa ... and weeping figs (Ficus benjamina)? Huge, park-scaled trees complete with aerial roots.

Graf remarks in his introduction about the efforts made to correct errors in previous editions, using as his reference Hortus Third, the Royal Horticultural Society's `Dictionary of Gardening' and a number of other august references. He writes in a way that manages to be both authoritative and accessible - I sense a gentle humor, probably gained from trying to explain why you want to go into the jungles, mountains and deserts in search of new species. When I open the books I feel it's a little like having my father, an excellent gardener in his own right, talking me through the magic of the plants. And for me, that was worth the price then, and now.

http://www.amazon.com/Exotica-International-Encyclopedia-Near-Tropic-Photographs... ( )