Chilopsis is a monotypic genus of flowering plants containing the single species Chilopsis linearis. It is known commonly as desert willow or desert-willow because of its willow-like leaves, but it is not a true willow – being instead a member of the catalpa family. It is a small deciduous tree or shrub native to the southwestern United States and Mexico.
At maturity, Desert Willows typically reach heights of 15 to 20 feet. However, under optimal conditions, they can occasionally grow up to 30 feet. It often grows with multiple trunks unless trained otherwise. Its natural growth habit is somewhat irregular. The spread generally ranges from 10 to 15 feet though this can vary based on pruning practices and growing conditions. The bark is smooth when young, becoming fissured as it ages.
In its initial years, especially with adequate water and in favorable conditions, it can grow quite rapidly, potentially adding several feet per year. As the tree matures, its growth rate tends to slow down but still maintains a moderate pace compared to other trees of similar environments. The leaves are long, narrow, and willow-like, which gives the plant its common name. They are usually 3 to 6 inches long and can be either deciduous or semi-evergreen depending on the climate.
The flowers are trumpet-shaped, reminiscent of catalpa or orchid blooms, with a flared end. Each flower is about 1 to 1.5 inches long and can be slightly larger depending on the variety.The natural color spectrum includes white, pink ranging to lavender, and purple. Many cultivars have been developed with more intense or different shades, including deeper purples, pinks, and even bi-colored flowers.
Inside the trumpet, you’ll often find contrasting colors like yellow, purple, or maroon. The flowers have a subtle, pleasant fragrance which attracts pollinators but isn’t overpowering. Desert Willows bloom from late spring to early fall, with peak blooming often occurring in late spring to early summer. In favorable conditions, some trees can have sporadic blooms throughout the growing season.
The flowers are particularly attractive to hummingbirds due to their tubular shape and nectar content. They also attract bees, butterflies, and other pollinating insects.
The fruit of the Desert Willow is a long, narrow pod. These pods are cylindrical, slender, and elongated, often looking like beans or small cigars. They can grow to lengths of about 6 to 12 inches. Initially green, they mature to a brown color. The pods are initially soft but become woody and brittle as they dry. Inside each pod, there are numerous small, flat seeds, each with a wing-like structure to aid in wind dispersal.
Desert Willows thrive in arid to semi-arid environments, tolerating both heat and drought well. They are often found in washes, canyons, and along streams where water is more accessible. They can live for many years, with some reports of trees reaching over 100 years, although this is less common in cultivation and more in the wild where conditions might be more stable.
This plant is very adaptable to different types of soil and conditions, which aids in its growth versatility, but extreme conditions like prolonged drought or very cold winters might affect growth rates or cause leaf drop.
There are several named cultivars of Desert Willow that have been selected for their superior flowering characteristics, such as ‘Bubba’, known for its large, burgundy flowers, or ‘Art’s Seedless’, which produces fewer or no seed pods, focusing more on flowering.
They are popular in xeriscapes, parkways, and as ornamental trees due to its attractive flowers and form. It’s used for creating privacy screens, as a specimen plant, or in naturalized landscapes. Provides nectar for pollinators and its seeds are food for birds like finches.
Cultivation
- Temperature: It thrives in hot conditions, which can enhance its growth rate, but it also tolerates cooler temperatures to an extent.
- Watering: While drought-tolerant, young trees benefit from regular watering until they are established. Once mature, they require minimal supplemental water.
- Care: Pruning can help maintain shape and encourage more flowering. It’s relatively low maintenance, making it a great choice for xeriscaping or in water-conserving landscapes.
- Fertilization: Although not always necessary, a light application of a balanced fertilizer in spring can enhance vigor and flower production, especially in nutrient-poor soils.
- Pests & Diseases: Generally pest-resistant, but can be susceptible to spider mites, whiteflies in stressed conditions, and sometimes root rot from poor drainage.
- Propagation: Can be grown from seeds or cuttings. Seeds need cold stratification to germinate.
- Pruning: Pruning can stimulate more flowers. Cutting back after the initial bloom can lead to a second flush of flowers. Deadheading, or removing spent flowers, can also encourage continued blooming.