Choose tropical ornamental plants for USDA Plant Hardiness Zone 9 carefully. Although Zone 9 is characterized by a long growing season with hot summers, its mild winter season does see an occasional freeze. Tropical plants that flourish in zones 10 or 11 are too tender, but there are many choices available that are well suited to a Zone 9 landscape.
The pindo palm (Butia capitata), also known as jelly palm, is a medium-sized, single-trunked, upright palm tree with a strongly curved canopy of leaves. Pindo palms grow up to 30 feet tall, but are commonly seen 10 to 20 feet tall. The trunk of a pindo palm has boots (old leaf bases) that remain on the tree, giving it a rugged appearance. Grow pindo palms in full sun on various soils. Pindo palms tolerate windy, hot conditions. The small fruit of pindo palms is edible.
Bird of Paradise
Bird of paradise (Strelitzia reginae) is an evergreen perennial or shrub with a clumping, trunkless form. It reaches a height of 4 feet, though it grows slowly and has equal or more spread. Bird of paradise leaves are long and waxy, 6 inches long with 1 1/2-inch-long petioles. Its large flowers are very unusual, with fused blue petals and long orange sepals, and appear like a bird in flight. Bird of paradise blooms throughout the year. Grow this tropical plant in light shade, on nutrient-rich, acidic, moisture-retentive soils. Plant bird of paradise in protected locations because Zone 9 is their upper hardiness limit.
Crinum lilies (Crinum spp.) are large clump-forming perennials with variable growth by species, but grow 5 feet or more, rapidly. Its leaves are light green and strap or sword-like, up to 5 feet long and 4 to 5 inches wide, and spirally arranged. Crinum lilies have long flower stems that grow from the center of the foliage with large, sometimes fragrant, trumpet-shaped flowers in shades of pink or white. Grow crinum lilies in full sun on various soils.
Cannas (Canna x generalis) are very tall, upright perennials, usually with single main stems and are heavily foliated with simple, up to 2-foot-long, spirally arranged leaves. Canna foliage color varies by cultivar, from green to red-purple and variegated. Canna flowers are very showy, up to 18 inches tall and 6 inches across, available in shades of red, pink, white, yellow or striped. Grow cannas in full sun or light shade on various well-drained, nutrient-rich soils.