GARDENING : EXOTIC PLANTS BRING BEAUTY, BEAR FRUIT IN VALLEY CLIMATE.

Byline: Joshua Siskin

Judy Rosen lives in the Sherwood Forest area of Northridge with one duck, six hens, 50,000 honey bees and a collection of exotic plants that cause discriminating botanists to cluck and buzz with delight.

I was called out to examine Rosen's newly acquired tree tomato. The tree tomato (Cyphomandra betacea) is a perennial that, planted from a seed, takes two to three years to produce fruit. It may also be propagated from shoot cuttings. Native to Peru and Brazil, it is related to the everyday backyard tomato; both are in the Solanaceae of nightshade family. The tree tomato, however, can grow to a height of 6 to 10 feet.

Its fruit is egg-shaped, reddish brown and faintly striped. The skin or rind is thick and tough, and is typically peeled when the fruit is eaten fresh. The fruit may also be stewed or made into jelly. Do not grow the tree tomato in the hottest part of your garden; a western or eastern exposure is preferable to a southern one.

Another egg-shaped fruit that Rosen grows is that which comes forth from the passion vine (Passiflora). Not all passion vines bear fruit, so check with your nursery to make sure the species that is carried or ordered for you is a fruitful one. If you find the right species, you will be rewarded with lots of passion fruit without much effort.

A warning: Passion vines are subversive and invasive, with a tendency to self-sow anywhere and everywhere. They have tendrils like cucumber and grape vines and an ability to climb rapidly and surreptitiously so that, before you know it, you see their orange fruit dangling from the top of a 30-foot tree, wondering what alien from another planet placed it there. The flowers of the passion vine, in their intricate patterned symmetry, produce kaleidoscopic effects.

Adjacent to her passion vine is a Surinam cherry (Eugenia uniflora). This is actually an ornamental shrub that produces spicy crimson fruit. It grows well in containers or planted in the ground, and may be used as a fruit-bearing hedge.

The tree tomato, passion vine, Surinam cherry and other exotic fruits may be found at the Papaya Tree Nursery in Granada Hills. For information, call [phone].

In one corner of her yard, Rosen has two trees that have distinctively feathery leaves, come from the same part of the world, and deserve wider use. One is the Chinaberry (Melia Azederach) and the other is the China Doll (Radermachera sp.).

The Chinaberry has fragrant lilac-colored flowers that are blooming now. Its foliage is a more delicate, lusher version of that seen on an ash tree and its bark is a deep shade of brown, hinting at its close relationship to the mahogany tree.

In Southern California, the Chinaberry is one of the smallest shade trees you'll see. It is deciduous and pest-free. One of its relatives is the neem tree (Azadirachta indica), from which an oil is extracted that has powerful insecticidal properties, inhibiting activity of scales, whiteflies, mealy bugs, termites, cockroaches and flies. Long used in tropics, neem products have only recently begun to appear in this country.

China doll, which has the laciest of lacy leaves, is a popular indoor plant that, on rare occasions, is seen outdoors. The most famous local specimens, which have grown to over 20 feet tall, may be found in the Asian section of the Los Angeles County Arboretum.

Rosen has a driveway with a 2-foot-wide planter strip running down the middle. In this planter, there is a variety of low-growing plants, including sweet alyssum, the purple miniature Swan River daisy (Brachycome), thyme and lamb's ear. What a nice alternative to the ordinary slab of concrete or asphalt!

Along the side of the driveway, in the shade, is a large lemon verbena (Aloysia triphylla) - a plant that caresses the nostrils of fragrant leaf lovers everywhere. Two other shade-tolerant herbs in Rosen's garden are comfrey (Symphytum officinale) and bee balm (Monarda didyma).

Rosen has needed bee balm, on occasion, since she likes to walk around on bare feet and steps on bees, every now and then. Some years ago, she came upon a swarm of honey bees in her lemon tree. This incident quickly turned her into an apiculturist, and she has been harvesting honey from several backyard hives, containing tens of thousands of bees, ever since.

Tip: Plant zinnia seeds now for summer harvest of a rainbow-colored assortment of blooms. Zinnias take heat without any trouble. They also make long-lasting cut flowers for vase arrangements.

MEMO: Joshua Siskin's column appears every Saturday. He welcomes questions from readers. Write to him in care of the Daily News Features Department, P.O. Box 4200, Woodland Hills, Calif. 91365-4200. You can also reach him through this on-line mailbox: JoshSiskinaol.com.