Decaisnea Drawing by Rene Eisenbart

BOTANICAL NAME: Decaisnea fargesii SOUNDS LIKE: Repays me a Parcheesi tie COMMON NAME: Blue bean shrub Type: Arching and upright deciduous shrub; 15 feet BASIC NEEDS: Sun to part shade WORST ENEMY: Nasty dense soils and bad pruning; keep plant open and airy. BEST ADVICE: Great for a raucous mixed border

Deciduous shrub

I have before me three fat, blue-stained bean pods the size of a large man's index finger. Their color is somewhere between washed denim and slate. Their two-day-old sagging flesh is eerily humanoid to the touch. They are, in a word, startling.

In the interest of science, I will now pop one of these decadently ripe pods open. Yuchh. (You'd better put this aside for later reading if you're about to eat). Inside, several dozen black beans are suspended in a liquid that looks like clear phlegm. Truly gross. But you haven't heard the half of it: I am now going to stick my finger in the goop and put it into my mouth.

Hmm. Not bad. Actually, quite sweet. In fact, sort of watermelon-like, in a gelatinous way. Good enough to spread on a little toast, if you could do something about the color. Or, if you had grown up where it was native - such as China's Sichuan province - you might even slurp it straight from the pod.

Introducing Decaisnea fargesii. One look at its fall fruit, and you'll never forget the color (I'll understand if you forgo the taste). Trust me, if you've any sense of wonder - or humor - you're going to want this shrub when you find out how easy it is to grow.

D. fargesii comes from a family of plants known largely for its vines, including Akebia and Holboellia. It's tall, lanky, and arching to about fifteen feet, with blue-green pinnate leaves and an informal effect just this side of tropical (like a better-behaved tree of heaven, Ailanthus). Though it's perfectly good-looking, I wouldn't say it's a stand-alone specimen, but its airy presence invites all sorts of underplantings, be they shrubs, perennials, or bulbs.

One of the best uses of this plant I've seen is in a parking strip in Portland, Oregon, where several specimens are spaced along the length of the street, mixed with innumerable - and largely deciduous - companions. The blue bean shrubs are intriguing in spring, with foot-long, drooping panicles of yellow-green flowers, and make attractive foliage fillers when the days grow hot. But it's after the parking strip loses its leaves that the iridescent, four-inch fruits come into their glory, suspended in midair like spray-painted sausages, a joke left over form Halloween.

All you need to grow the plant successfully is full sun to part shade, good loamy soil, and a site no more hospitable than a curbside. Then, come next fall, after you've slurped out the fruit's innards, you can plant the magic beans.