Tropical plants are hardy in a small area of Arizona in the southwest where the climate replicates the climate of their native habitats. Tropical plants bring a splash of color, and in some cases edible fruits, to the garden and thrive side by side with native plants of Arizona.
Bird-of-paradise (Strelitzia reginae) is also known as the crane flower, and is native to South Africa. The plant grows from 3 to 5 feet tall and features leaves that feel like leather that grow straight up on stiff stalks and grow up to 18 inches long and 6 inches wide. The flowers are made up of blue petals and orange sepals--leaf-like parts that protect the flower when it is a bud and surrounds the flower when it is open. The arrangement looks like a bird in flight. Plant the bird-of-paradise in full sun and the plant will be shorter. Plant it in partial shade and it will be taller and the flowers will be larger. The leaves do not fall off, making the bird of paradise a good choice in the pool area.
Orchid tree (Bauhinia variegata) is also known as the purple orchid tree, mountain ebony and the poor man's orchid. The tree is native to northern India, Vietnam and southeastern China, grows from 20 to 40 feet tall and has a spread of 10 to 20 feet. The leaves are round and grow from 4 to 6 inches across. The flowers resemble orchids, grow from 3 to 5 inches across in clusters at the tips of the branches and come in magenta, lavender or purple-blue and bloom from late winter to early summer. The flower produces flat seed-pods that grow up to 12 inches long. Plant the orchid tree in full sun and a moist soil. The tree is hardy in the southwest corner of Arizona in zones 9 and 10 where the temperatures do not go below 22 degrees F.
Lychee (Litchi chinensis) grows from 40 to 50 feet tall with a spread of 20 feet. The tree produces leaves that start out as bronze-red and turn to a dark glossy green and grow from 3 to 6 inches long. The small yellow flowers bloom in the early spring, growing in clusters that grow up to 12 inches long. The flowers give way to red, edible fruit in the later part of June and July. Plant the tree in full sun in a fertilized, well-drained soil. Lychee is hardy in southwest Arizona where the nighttime winter temperatures do not get below 30 degrees F.