THE TOPIC OF killing slugs with homemade beer traps is what really gets the audience chuckling—this assemblage of Portland garden enthusiasts with wash ’n’ go haircuts and shoes more sensible than stylish. At Powell’s Books in Beaverton, Jeff Gillman, the evening’s speaker and the author of The Truth About Garden Remedies and The Truth About Organic Gardening, has just related one of his slug-offing secrets: “Slugs actually prefer dark ale. I like to use Moose Drool myself.” If your goal is to destroy the pests, Miller Lite just won’t cut it.

Gillman, an associate professor of horticultural science at the University of Minnesota, is one of the top-selling authors for Timber Press, the Portland-based publisher of horticultural books. An affable, if folksy, public speaker, Gillman also is one of the first authors the press has ever sent on a promotional book tour (though at five cities, it is, admittedly, a short one). A Barnes & Noble buyer, pleased with the provocative titles of Gillman’s books and their customer-friendly price point of $12.95, even saw fit to place them on the chain’s spring garden table—which all but guaranteed that a couple thousand additional copies would be sold.

In the business of selling books, author tours and good product placement hardly count as marketing innovations. Nevertheless, they represent a big shift for Timber Press, which was until recently an independent publisher that marketed its books almost exclusively at botanical gardens, gardening trade shows, and gardening stores—venues where plant geeks hang out.

But in fall 2006, Workman Publishing, a New York City-based publisher with five imprints, acquired the 28-person company, and since then has encouraged Timber Press to expand its audience partly by increasing its access to distribution channels at bookstore chains.

Yet what is most impressive about Timber Press is not how much it has changed since it was founded by local bookseller Richard Abel in 1978, but how little. That was the year it released a 178-page monograph by entomologist J.D. Vertrees called Japanese Maples, which sold for the then-outlandish price of $40 (and which is slated to be released in its fourth edition next summer). It turned out there were maple freaks aplenty who bought the tome, which had been rejected by a dozen other publishing houses.

Soon after, Trees and Shrubs of Temperate Climates, Lilacs, and Orchid Species Culture came out, all of which helped establish Timber Press’s formula for success: Publish authoritative guides by plant experts, not “writers,” and pack the pages with luscious photographs of plants, whether the book’s subject be clematis, mushrooms, sweet pea, or slime molds. “We call them ‘information rich,’” says publisher Neal Maillet, rejecting the idea that they are for reference alone. Such books are expensive to publish, and print runs rarely hit five digits. (Japanese Maples has sold about 65,000 copies in 40 years; Harry Potter and the Deathly Hallows, by comparison, sold 8.3 million copies in one day.)

Today, producing pricey books with small print runs is an anomaly in the $25 billion book publishing industry. Publishers and booksellers have bought each other up so many times in the past two decades that calling them megalithic is not hyperbole. (Last May, No. 1 bookstore chain Barnes & Noble announced it would consider buying No. 2 Borders.) The result has been a Hollywood-esque business model of books, one that relies on blockbusters and trend-chasing to feed the bottom line.

All the while, Timber Press has quietly toiled away in a downtown building on SW Second Avenue, churning out books for a specialized market—a tenacious approach to publishing that has guaranteed its long-term success. It now has some 450 titles in print, and $5 to $10 million in annual sales (up from less than $1 million in 1989). While many popular books about plants tend toward what Washington Post garden columnist Adrian Higgins calls “personal narratives; people discovering themselves in the garden—a kind of memoir,” Timber Press has not jumped on the trend, preferring to stick to its roots.

“I’m a salvia nut, and they publish the definitive work on salvias,” notes Amy Stewart, one of the founders of horticultural blog Gardenrant.com. “If there’s a new edition, I just have to have it.” And unlike many consumers, who seem to suffer from attention spans so short that reading itself has become a thing of the past, the gardening audience has a loyalty to the printed page. “We are a very tactile people,” Stewart says. “We still have an appreciation for a dog-eared book.”