Mexican bird of paradise is a small tree that stays green and flowers all year long. Here’s everything you need to know about planting and caring for this Sonoran Desert native.
Mexican bird of paradise (Erythrostemon mexicanus) is a small evergreen tree native to parts of Mexico and Texas. Its bright green leaves are fern-like. Its slightly fragrant flowers are lemon yellow and bloom much of the year.
This tree may look lacy and delicate, but it’s a tough desert plant that is exceptionally heat tolerant and thrives in full sun or reflected heat. It is cold hardy down to 15℉ but can experience some cosmetic damage to leaves at around 25℉.
Mexican bird of paradise is a low-maintenance tree. It needs minimal irrigation, pruning, and fertilizer, and produces minimal litter.
Unlike the red of paradise commonly found in southwest gardens, this species has no thorns.
When in bloom, its flowers attract hummingbirds, butterflies, bees, and other nectar-seeking insects. Birds are attracted to the seeds. Javelina, deer, and rabbits generally leave it alone.
Why I Like This Plant
- Charming small evergreen tree
- Vibrant yellow flowers that bloom much of the year
- Unlike the other birds of paradise, it has no thorns
- Low maintenance, low water, low litter
- Flowers attract butterflies, hummingbirds, bees
Things to Watch Out For
Birds of paradise are often toxic due to their high levels of tannins and Mexican bird of paradise is no exception. The University of Arizona lists it as poisonous, and the ASPCA lists a related species as toxic to dogs, horses, and cats.
I would err on the side of caution and assume that it’s toxic to both humans and pets, especially the seeds and seed pods.
Optimal Growing Conditions
If you are thinking of adding a Mexican bird of paradise to your garden, you need to find a suitable place that will keep your plant healthy and looking good… while minimizing maintenance for you.
Here are the key factors to keep in mind.
Temperature
Mexican bird of paradise should be grown in USDA Hardiness Zones 8 – 11. It has a very high heat tolerance and can be grown in the hottest locations of your yard.
It is cold-hardy down to 15℉. While it’s considered evergreen, it’s normal for it to lose some leaves once the temperature dips below 25℉. But no worries if it gets zapped by cold, it quickly rebounds in the spring.
Sun Exposure
Mexican bird of paradise thrives in full sun and doesn’t mind the reflected heat from a west-facing wall. While it can be grown in part shade, you can expect to see fewer flowers, and they will be less colorful.
Size and Growth Rate
Mexican bird of paradise is considered a moderate-to-fast grower. This tree stays small and when mature it will reach a size of 5 – 10’ wide by 15’ tall.
Soil
Mexican bird of paradise is not fussy about soil and grows well in any soil — sandy, rocky, clay — and even the poorest desert soil, provided it’s well-draining.
Mexican Bird of Paradise:
The Essentials
| Common Name | Mexican bird of paradise |
| Scientific Name | Erythrostemon mexicanus |
| Origin | Mexico, Texas |
| Plant Type | Evergreen tree |
| USDA Zones | Zones 8 – 11 |
| Cold Hardy | To 15℉ |
| Flower Color | Yellow |
| Flower Season | Spring, summer, fall |
| Mature Size | 10-15’ high x 5-10’ wide |
| Growth Rate | Moderate to fast |
| Sun Tolerance | Full, part, reflected sun |
| Water Needs | Low |
| Pests & Diseases | None |
| Toxicity | All parts toxic |
| Garden Friendly | No thorns |
| Wildlife | Attracts butterflies, hummingbirds, bees |
Other Location Considerations
Seed pods form in the spring. Not everyone is fond of their appearance, and they can be somewhat messy. Additionally, the seed pods are toxic. For these reasons, don’t plant it near a pool or in an area where children or pets might be able to access the pods.
How to Plant
The rule of thumb when planting any tree in the desert is to dig a hole three times as wide as the root ball but no deeper. Amending the soil is not recommended. Counterintuitively, backfilling with the same native soil you just dug up helps your plant develop a stronger root system.
When to Plant
The best time to plant Mexican bird of paradise is in the fall. This gives your plant three seasons to grow roots and get established before the following summer.
The second best time is in spring, the earlier the better. This still gives your plant time to get established before the intense heat of June arrives.
How to Care for Mexican Bird of Paradise
Whether you’ve recently planted a new Mexican bird of paradise or have an existing one in your yard, here’s how to take care of it to keep it healthy and looking its best.
How to Water New Plants
Once you’ve got your tree in the ground, watering is your most immediate concern. Here is the recommended watering schedule for new trees planted in the spring or fall.
| Weeks 1 & 2 | Every 3 – 4 days |
| Weeks 3 & 4 | Every 6 – 7 days |
| Weeks 5 & 6 | Every 7 – 10 days |
| Weeks 7 & 8 | Every 10 – 14 days |
After week 8, gradually extend the time between waterings.
How to Water Established Plants
As your tree becomes established, there are two watering factors to consider.
- First is how often to water. This will vary with the seasons.
- Second is how much water to give your tree with each watering. This depends on the current size of your plant.
To determine the ideal watering schedule for any desert tree, you’ll find everything you need to know, including easy-to-use charts, at How to Water Desert Trees: How Often? How Much?
Should You Fertilize?
While you can fertilize Mexican bird of paradise, you certainly don’t have to. They get all the nutrients they need from our native soil. And since they are a member of the legume family (Fabaceae) they fix nitrogen which naturally improves their surrounding soil.
How to Prune
Mexican bird of paradise doesn’t need much pruning. In the spring, remove any branches that were frost-damaged.
Since it naturally grows as a multi-trunk tree, your plant might send up more shoots than you want. You can simply snip them off at the base while they are young.
The Many Birds of Paradise: It’s Confusing
There is a lot of confusion between the various bird of paradise species used as landscape plants. This is in part because they all have many common names, and sometimes there is overlap.
Unfortunately, several species are referred to as simply “bird of paradise” which leads to further confusion.
Additionally, I’ve been dismayed to see that many gardening sites and internet search engine results have the various bird of paradise species all mixed up!
Here’s a quick rundown of similar bird of paradise species.
Red Bird of Paradise (Caesalpinia pulcherrima) is a very common landscape plant. It grows as a very large shrub with showy, multi-colored, yellow to red flowers. Once you know the difference, you’ll notice it doesn’t look much like Mexican bird of paradise.
Yellow Bird of Paradise (Caesalpinia gilliesii) grows as a shrub and looks similar to the red bird of paradise, except it’s yellow flowers have very prominent red stamens, as you can see in this picture.
And finally, there is the tropical bird of paradise (Strelitzia reginae) which has exotic, orange, blue, and white flowers that look like a bird. Before moving to the desert, this was the only bird of paradise I was familiar with.
Mexican Bird of Paradise: Names Abound
Mexican bird of paradise goes by a multitude of common names including Mexican holdback, Mexican caesalpinia, yellow bird of paradise, yellow bird, Mexican poincianella, Mexican caesalpinia, and Mexican poinciana.
Additionally, the Mexican bird of paradise has undergone many scientific name changes. The correct name is now but the former name Caesalpinia mexicana is persistent and still commonly cited.
Other scientific names used in the past that still linger in scientific literature include Caesalpinia robinsoniana, Poinciana mexicana, and Poincianella mexicana. Some of these names go back to the 1800s.
No wonder people are confused about the birds of paradise!
This demonstrates why the use of a currently accepted scientific name to properly identify a plant can be important.
Did you enjoy this article?
Sign up for our weekly newsletter
where you’ll find more great info on creating &
maintaining a beautiful, carefree desert landscape.
Author Bio
Deane Alban is the creator of Southwest Gardener. She is a science writer with a bachelor’s degree in botany from the University of South Florida. Gardening is her lifelong passion. She’s been gardening in Tucson for 15 years.
Additional Reference
Photo Credit
Consultaplantas, CC BY-SA 4.0, Wikimedia Commons