HALLOWEEN HAS LONG BEEN my favorite holiday. There are few expectations - no big meals to cook, no gifts to buy, no eggs to hide - just a spooky celebration of the turning of the season, the last of the leaves, the plunge into winter.

In recent years I have expanded my decorating from a twisted, bare-twig wreath by the door and a pumpkin-headed stuffed man to greet trick-or-treaters, out into the garden itself. The texture of tree bark on bare branches etched against the early darkness of the sky, thorns, berries, gnarled vines now bare of foliage - all become ominous once you get into the Halloween mood.

I found inspiration for this celebration of nature's less obvious charms a few years ago at a Northwest Flower and Garden Show display designed by Dan Borroff, with plants supplied by Peter Ray (Puget Garden Resources on Vashon Island) and Dan Hinkley (Heronswood Nursery in Kingston). Titled "It Was a Dark and Stormy Night," this murder-mystery set of a garden was filled with thorns, dark leaves and gnarled branches, all creating a creepy graveyard ambience.

All this atmospheric creativity sprang from practicality.

"We had forced plants for the show two years previously and had a technical breakdown," said Borroff. Half the plants perished, and the team wasn't eager to repeat the uncertainties of forcing. "We decided to use what looks good in the winter and make the most of it."

Good advice not only for a five-day display garden, but for an entire season in our home gardens.

"Breezy romance novels and summer vacation work, but are far too `pretty' for winter," Borroff says. "I'd rather curl up with a mystery on the sofa, branches and vines knocking against the house in the rain. It's a far better fit with the mood of the season, don't you think?"

Perhaps the most obvious way to create a feel of foreboding is to use a carnivorous plant or two. While the native habitat for these open-mouthed exotics are steamy swamps, pitcher plants (Sarracenia) can survive outside as far north as Vancouver, B.C. Flies, ants and wasps fall drunk to their deaths after following trails of intoxicating nectar down into the plant's dark-veined throat. The better-known Venus flytrap tolerates light freezes; skinny teeth line its clamshell-shaped halves and snap shut once an insect enters, holding it captive until drowned in the plant's digestive juices. If you are interested in creating a Little Shop of Horrors in your own garden, take a look at the book "The Savage Garden" by Peter D'Amato (Berkeley, Ten Speed Press, 1998).

It was with anticipation of the dark, windy days of autumn that I planted a `Little Prince' Corokia in my rockery this September. It is drought-tolerant and likes bright sun, so is ideal for this exposed slope, but I really chose it for its bizarre appearance. Growing 3 to 4 feet high, it resembles nothing more than a wild snarl of snaky, gray witches' hair. It's surrounded with arching brown clumps of leather-leaf sedge (Carex buchananii); the two mingle in an eerie tangle for Halloween.

If we were choosing spooky plants on name alone there is a garden-full of candidates: witch hazel, devil's comb, creeping toadflax, stinking hellebore, blood sedge, pig's squeak and dead nettle, to name a few.

Some of these plants are seriously creepy; others reveal their most dramatic characteristics beneath gloomy skies or the golden shine of the harvest moon:

-- Miss Wilmott's Ghost (Eryngium giganteum) is a biennial with white, spiny flower heads, uncannily pale and jagged in the moonlight.

-- Dragon arum (Dracunculus vulgaris) smells and looks like something that has pushed its way up through the earth all the way from the underworld. Black-red hooded flowers and a long black tongue (is it forked?) complete the disgusting picture.

-- Ghost bramble (Rubus biflorus) has ghostly canes arching to 6 feet. After the leaves drop off in the fall, the tangle of stems glow snow-white through the winter.

-- Rosa sericea pteracantha has thorns every bit as intimidating as the thought of trying to pronounce its name. Winged thorns of deep and glowing red line the stems, abruptly and sharply pointed as a vampire's fingernails. Oh, and it has creamy single flowers in early summer, too.

-- Solanum pyracanthum has aggressively sharp orange thorns thickly lining the stems, toothed foliage and pretty purple flowers. Its air of spiky malevolence makes it hard to believe it is a member of the humble potato family.

Valerie Easton is a horticultural librarian and writes about plants and gardens for Pacific Northwest magazine. Her e-mail address is vjeaston@aol.com Richard Hartlage is a Seattle horticultural photographer.

Now In Bloom: Sweet gum (Liquidambar) holds its maple-like leaves longer into the fall than most other trees. `Orientalis' grows to 20 to 30 feet, with leaves that turn deep gold to bright red and even purple, sometimes carrying all colors at once on the same tree in a symphony of autumnal elegance.