E.J. Hook, Woodland Park Zoo's new landscape manager, is charged with maintaining a natural environment that can survive the animals it's meant to nurture.

For too many years, zoos housed animals simply in cages, arranged in categories dreamed up by taxonomists. No matter what their natural habitat, monkeys were displayed with other monkeys, all the big cats were side-by-side. The Jones and Jones Master Plan, completed in the mid-1970s, was revolutionary in its call for bioclimatic zones, allowing animals to live in realistic groupings.

How to mimic or simulate natural environments from around the globe? Zoo horticulture came to the forefront, as plants were used to tell the story of these different regions. What a challenge for zoo horticulturists, charged with searching out plants that would survive beyond the reach of an elephant's trunk or a gorilla's capacity for play. The gardeners quickly came to know each species' eating and living habits. Plants had to simulate a variety of natural environments, but survive outdoors in Seattle with minimal care. Hence a magnificent display of cleverly designed plantings, now lusciously matured, inside and outside the exhibits.

Animals are complicated creatures, so living in familiar environments has greatly improved their quality of life. The plants provide privacy, playthings (take a look at what the orangutans have done with their trees!), food and shelter. Visitors watching zebras graze can feel the heat shimmering off the African savannah, or a few steps away can absorb the dripping hush of a sultry rainforest. Such immersion causes us to share an animal's world. At the same time, we can see some pretty cool plants, used so skillfully they can even trick us into thinking we've escaped the Northwest.

Now In Bloom The large, scalloped leaves of Crambe maritima might be mistaken for a dramatic cabbage if not for their elegant blue-green sheen. A hardy perennial, this sea kale grows 2 feet tall and wide, with clusters of white, honey-scented flowers in summer.

E.J. Hook, the zoo's new landscape manager, loves the unique challenges of his job. "Here, the plants get touched, by people and animals," says Hook, whose previous job was working on far less intensively used landscapes for Seattle City Light. As we walked through the zoo together on a sunny afternoon, Hook pointed out the many roles plants play in this landscape. The thick mix of foliages screen views and muffle noise so that even on a typical day, when 6,000 to 9,000 people visit the zoo, each can feel a connection with the animals and perhaps find a moment of solitude. Most of the plants are broad-leafed evergreens that provide sturdy good looks year-round, such as viburnum and nandina, with some mammoth-leafed gunnera, fuzzy kiwi vines and spiky flax or yucca blended in for exotic flair.

While your kids enjoy the emus and wallaroos, you can check out the just-planted Australian hillside to find hardy, drought-tolerant species, and see how good tree ferns and eucalyptus look mulched with gravel. If you want to create a mountain look beyond the usual Douglas fir and sword ferns, 60 of the 128 species native to Alaska grow in the Northern Trail exhibit.

This heavily planted 92 acres also offer gardeners a lesson. No herbicides are used inside the exhibits, and outside only as needed; Hook plants reduce chemical use throughout zoo grounds. The main technique is to plant so thickly that weeds are discouraged, and those that make it through are barely noticeable. "Manicured is not what it's about for us — the survival of the fittest, as we mostly let the plants alone to grow into their own natural shapes," says Hook. "We mimic nature, and then let nature take its course."

Valerie Easton is manager at the Miller Horticultural Library. Her book, "Plant Life: Growing a Garden in the Pacific Northwest" (Sasquatch Books, 2002) is an updated selection of her magazine columns. Her e-mail address is vjeaston@aol.com. Barry Wong is a Pacific Northwest magazine staff photographer.