Tropical Plants in Oregon

Palms

• Few plants give a garden a more tropical look than a palm. The windmill palm, Trachycarpus fortunei, hardy to zone 7, is the hardiest tree-type palm, native from central China to Burma, and does well in partial shade. The Mediterranean fan palm, Chamaerops humilis, is hardy in zone 8, surviving temperatures down to 10 degrees and prefers bright sun. The needle palm, Rhapidophyllum hystrix, is the most cold-hardy palm in the world, with clumps of fan-like foliage that withstand sub-zero temperatures.

Bananas

• Another quintessentially tropical plant is the banana, and there are several hardy species. The hardiest is the Japanese fiber banana, Musa basjoo, which can be grown in zone 4b. The dwarf Chinese banana, Musella lasiocarpa, has showy yellow flowers and is hardy to zone 6.

Flowers

• You can grow Cannas as perennials in zone 8, especially in a warm spot, in moist or wet soil. Their bold, bright flowers and large leaves make them excellent focal points for a tropical garden. Also a stand-out for its large flowers is the hardy Hibiscus, Hibiscus moscheutos, or rose mallow. Colors range from white to deep-rose and, as its common name indicates, it prefers moist soil.

Trees And Shrubs

• The wonderfully fragrant gardenia, Gardenia jasminoides, has a few forms that are hardy in zone 7: 'Kleim's Hardy', 'Frost Proof', and 'Chuck Hayes'. Give them acidic soil and excellent drainage. Night temperatures in the mid-50's are necessary for forming buds.

  The crepe myrtle, Lagerstromia indica, has showy panicles of flowers in summer and fall and can substitute in temperate climates for the tropical species, L. speciosa, a common sight in Hawaii and other tropical areas.

  The silk tree, Albizia julibrissin, a hardy member of a mainly tropical and subtropical family, has fern-like leaves and puffy pink flowers that are lovely paired with bright annuals and bold leaves.

Bamboo

• Bamboo, a large woody grass, gives an Asian, exotic air to a garden, and there are many types hardy in Oregon. The common golden bamboo, Phyllostachys aurea, can be invasive and should only be planted inside a metal barrier, but there are others, such as the black bamboo, Phyllostachys nigra, that spreads slowly and is an excellent ornamental for tropical gardens.