WRITTEN BY VALERIE EASTON

		"Flora: A Gardener's Encyclopedia," in two volumes (CD edition available), Timber Press, 2003, $99.95.

Think of it in terms of amortization, like those wardrobe people say you should do with clothes. You're supposed to divide the purchase price by the number of wearings to calculate the value of a piece of clothing; you may have paid only $50 for that misguided miniskirt, but it really cost far more than the expensive cashmere sweater you wear three times a week. Believe me, you'll refer to "Flora" more often than any other gardening book on your shelves.
 

A hybrid cultivar of clematis (Forsteri Group) from New Zealand is just one of the hundreds of clematis that "Flora" shows in color photographs.
Even though editor Sean Hogan says trees and shrubs are emphasized, plenty of perennials such as these lupines are included.

So what, besides the fact that it's glossy, colorful and big, makes this book so exceptional?

First, it is the newest and most complete plant-reference book around, so a great number of the freshest, most exciting species and cultivars are included. Dozens of dark-leafed dahlias are listed, the photos of blowsy, exotic tree peonies are irresistible, and there's a gallery of unusual zinnias. Salvia, pines, rhododendrons and iris, too. There's no way this book won't enchant you with the sheer number of plants, plentifully photographed. When those enticing new plants are described but not pictured in the hottest catalogs, you can turn to "Flora" and actually see many of them.

I admire how complete the book is as much as how well-designed it is. The index and glossary are extensive, and so far appear to be accurate. If you've never quite figured out what a "simple umbel" looks like, clear color drawings show the many types of leaves, fruits and flowers. For those of you not quite as entranced by the inclusiveness of reference books as I am, there's the flashy green cover, easy-to-use page tabs and color photos on every page, used sufficiently large to capture the nature of each plant, often in each season.

This book is seductive for all kinds of reasons.

Perhaps its most original and inspiring attribute is that it is (forgive me if I over-enthuse here) the first truly international plant encyclopedia. It doesn't have the usual East Coast emphasis we've had to put up with, probably because its genesis was in Australia, and a team of international experts put the book together. Plants listed include those that in the past could be found only in exotica or books on houseplants, if they could be found at all.
 

			Now In Bloom Heuchera 'Obsidian' is a new coral bells cultivar with the darkest leaves yet of these deservedly popular perennials grown for their showy foliage. The scalloped leaves are a glossy ebony on top, a perfectly contrasting soft lavender underneath. Cream-colored, airy flowers appear in early summer. The leaves should persist all winter until cut back in early spring to make room for new leaves. Low-growing and mounding, it is ideal for containers or borders. H. 'Obsidian' needs moist but well-drained, fertile soil in sun or partial shade.

Because we can grow many New Zealand and Australian plants, it will be an especially useful reference for West Coast gardeners. And what makes the book a real bonanza for those of us gardening in the maritime Northwest is that the chief consultant on the book was Sean Hogan, who lives, gardens and runs a nursery and design business in Portland. Hogan says his biggest role was in applying the standard USDA zones around the world, and writing the introduction for North America that explains what zones and climate mean for gardeners. He applied the zones "with a caveat," meaning we'll find frequent comments like "needs heat to ripen," or "dislikes humidity" — the details we need to know to grow a plant successfully.

Hogan, a self-described "plant geek" since he was 3, spent several years coordinating "roving photographers and a sea of people gathering information around the world." He feels the book is distinguished by the sheer number of plants; you'll find more roses and more cacti listed than you'll see in books specifically on those plants. "No one believed a project this big could ever happen," says Hogan. Believe it, and you'll spend the winter happily, nose in book.

Valerie Easton is a Seattle free-lance writer and contributing editor for Horticulture magazine. Her e-mail address is vjeaston@aol.com.

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