You can have a lush, jungle-like garden right here in the Rogue Valley if you carefully choose broad-leaf evergreens for your landscape.
This group of plants holds their beautiful leafy foliage all year; and we are not talking about needle, pine-like foliage, but rather big and/or glossy leaves, the kind of foliage associated with Hawaii and other tropical landscapes.
The largest selections of cold-hardy evergreens are shrubs such as acuba, pieris, camellia, and rhododendron. All of these are easy to find in your local nursery. Plantings of these selections provide a good foundation for a green oasis that is beautiful year round, even in freezing weather. Such a garden paradise theme can be used throughout your garden or confined to one intimate area around your home.
Dale Sullivan, owner of Siskiyou Rare Plant Nursery in Talent, sells a wide variety of exotic plants that are surprisingly tolerant of our cold winters. He says nearly any broadleaf evergreen will give a tropical look to a landscape, and suggests the unusual such as hardy palms and cold-tolerant eucalyptus. These beauties will bring height and an upper level canopy to your "jungle garden." Hardy palms are especially useful since their slender trunks take up very little ground space and their unusual fan foliage creates an overhead leaf pattern most often associated with exotic tropical paradises. Sullivan sells two forms of windmill palm (Trachycarpus) which are hardy to Zone 7, 0 degrees F. Rarest of his palm selections is T. wagnerianus, which is quite a dwarf, only reaching 15 feet in height, and whose fans always display a very stately, rigid habit.
While most conifers won't do, two conifers from China must be recommended. Their oversized foliage provides the "Jurassic Park" feeling you should be seeking. Both grow into full-sized trees of 30 feet or more and are available in dwarf, prostrate varieties. The China fir (Cunninghamia lanceolata) with oversized needles is striking. The full-sized tree can also be found in a silver leaf variety. The deerhorn cedar (Thujopsis dolobrata) is a grand, but slow growing conifer with big "antler-like" cedar foliage. It will grow in sun or total shade.
In the world of unusual evergreen shrubs which lend that jungle-appearance, Sullivan says to look for the rare evergreen myrtle (Luma apiculata), Grevillea victoriae 'Marshall,' which displays clusters of slender, curved orange flowers winter and spring. The most unusual is a fruitless, ornamental hybrid fig (Ficus carica X pumila), with deep green lobed leaves (deciduous) and has both climbing and arching branches. Look for the large leafed ivy or Algerian ivy (Hedera canariensis), a tropical-looking groundcover; the striking variegated varieties will add brightness to your "jungle floor."
Don't neglect the spectacular perennial plants, many familiar, that add to the tropical look when combined with other "jungle plants." Some are evergreen like hellebores, with big palmate leaves, and cast iron plant (Aspidistra) with its long, tough, green leaves. Sullivan recommends the colorful variety A. lurida 'Ginga' with leaves heavily spotted with gold. Both these frost-hardy, evergreen perennials will grow in dry shade.
The herbaceous perennials that merit use include cannas, hostas, bletillas (hardy orchids), Begonia grandis, and begenia. The giant-leafed perennial known as "dinosaur food" (Gunnera manicata) with leaves to 4 feet or more across is for the larger tropical garden. All of these herbaceous selections will fill in and add extra lushness to the tropical-looking garden spring through fall, then go dormant for the winter.
Once you get started, you will have a ball discovering the probably hundreds of plants which can be effectively used in a Rogue Valley tropical garden. Have fun making choices and making your jungle paradise uniquely your own.