For summer color and attracting hummingbirds, the Caesalpinia species are an option. While none of these plants are native to Arizona, they are low water use. Which one is the best? It depends on what you are looking for. Low maintenance might be a priority; or maybe you prefer a plant that's not winter dormant. So how do you choose?
First of all, do not rely on a common name. They can be very misleading. One plant can have many common names. If you want the correct plant, you must rely on the Latin name. Using a plant's Latin name is the only way to be sure you are buying the plant you want.
Here's an overview of your choices:
Caesalpinia pulcherrima (RED BIRD OF PARADISE)
The Red Bird of Paradise is native to Mexico and the West Indies. It matures to about 6' tall and wide. However, since it is frost tender, it will freeze to the ground when temperatures go down to 30 degrees or colder. Once it freezes back, you will need to cut the plant to the ground. It will recover quickly once warm weather arrives.
The Red Bird is considered a low water use plant, surviving on weekly irrigation in the hottest part of the summer. Once established it may live on less, but if you want lots of flowers you will need to water it more.
Advantages: Colorful, showy red and orange flowers attract hummingbirds.
Disadvantages: Thorny, frost tender, and can become a pest. It will reseed everywhere if it is happy, and is difficult to remove.
Casesalpinia mexicana MEXICAN BIRD OF PARADISE
The Mexican Bird of Paradise is native to Mexico. This variety reaches tree size, maturing at about 10' tall and 8' wide. The flowers are yellow. It is cold hardy to about 15 degrees, and considered mostly evergreen. Unlike the Red Bird, it has no thorns.
The Mexican Bird of Paradise is also a low water use plant, but will do better with supplemental irrigation during the hottest part of the summer.
Advantages: Thornless, evergreen, attracts hummingbirds, requires little pruning.
Disadvantages: The seed pods are messy, and "explode" when they are ripe, scattering seeds everywhere. It does not seem to propagate itself as readily as the Red Bird, though.
|Mexican Bird of Paradise (Caesalpinia mexicana)|
Caesalpinia gilliesii YELLOW BIRD OF PARADISE
The Yellow Bird of Paradise is also not a native, as it originates from Argentina. It has naturalized here, however, making itself at home without becoming an invasive pest. This species matures at 6' tall by 5' wide, and is deciduous. While it will lose its leaves in cold weather, it does not freeze to the ground. Therefore, maintenance is minimal. It has the same water requirements as the other two varieties, but may survive on rainfall once established.
Advantages: Showy yellow flowers with red stamens attract hummingbirds and butterflies. Thornless. Very low maintenance.
Disadvantages: Winter deciduous.
|Yellow Bird of Paradise (Caesalpinia gilliesii)|
While we're on the topic of plants named Bird of Paradise, there's at least one more you may see in warmer parts of Arizona, or where there is significant frost protection.
The African Bird of Paradise hales from South Africa. Not a desert plant by any means, it is damaged at 28 degrees, and killed at 20. It prefers rich soil, ample moisture, and heavy feeding. Some plant parts are believed to be poisonous.