How to Grow and Care for Desert Willow

by Ken Lain, the mountain gardener

This Southwest native is the ideal summer-blooming tree for high-altitude landscapes. It features fragrant, trumpet-shaped flowers that attract hummingbirds, bees, and butterflies from spring through autumn. Large enough to provide dappled shade in a front yard and tough enough to handle the heat and wind of a desert mountain. Plant them as focal points, in groups for a natural screen, or near patios where the fragrance of the blooms can be enjoyed.

Quick Facts

·      Botanical Name: Chilopsis linearis

·      Common Names: Desert Willow, Desert Catalpa, Flowering Willow

·      Plant Type: Flowering Deciduous Tree

·      Mature Size: 15' feet tall x 10' feet wide (depending on variety)

·      Sun Exposure: 6+ hours of full mountain sun

·      Soil Type: Well-drained, sandy/native

·      Soil pH: 6.5–8.5 (Tolerates alkaline soils)

·      Bloom Time: Late Spring through Autumn

·      Flower Color: Pink, purple, burgundy, or white

·      Hardiness Zones: 7–11 (Can survive in Zone 6 with protection)

·      Native Area: Southwest US, Mexico

Desert Willow Care

Desert willow is a hardy, long-lived native that thrives in our intense Arizona sun. While it is extremely drought-tolerant, it requires deep watering during its first year to establish a strong root system.

·      Soil: Thrives in well-drained soil and actually prefers nutrient-poor, sandy, or rocky soil. Avoid heavy clay or sites where water stands, as soggy feet will lead to root rot.

·      Light: This tree craves the sun. For the best bloom production and a healthy canopy, ensure it receives at least 6+ hours of direct sunlight daily.

·      Watering: * April – Oct: Irrigate 1–2 times per week for new trees; established trees may only need a deep soak every 3–4 weeks during extreme heat.

·      Nov – Mar: Irrigate 1–2 times per month if the winter is dry.

·      Fertilizer: These trees are adapted to poor soils and don't need much. To encourage better blooms, use Watters 7-4-4 All Purpose Food in early spring and again in mid-summer.

How to Plant

1.    Dig a hole 2–3 times the width of the container but the same depth.

2.    Score the root ball sides and bottom and place in the hole with the root crown slightly above ground level.

3.    Blend Watters Premium Mulch with native soil (1 part mulch to 2 parts soil) and pack firmly.

4.    Sprinkle 7-4-4 All Purpose Plant Food around the planting area.

5.    Prevent 'Transplant Shock' by adding Watters "Root & Grow" to your water every 2 weeks for the first 2 months.

6.    Top dress with mulch to insulate roots, but keep the mulch a few inches away from the trunk to prevent rot.

Pruning

Desert willows naturally grow with multiple trunks and a shrubby habit. To achieve a more traditional tree-like form, prune the lower branches and suckers in late winter or early spring while the tree is dormant. A light summer pruning can also encourage a fresh flush of flowers, as they bloom on new wood.

Popular Varieties

·      Bubba: Known for its fast growth and large, fragrant burgundy/pink flowers.

·      Timeless Beauty: A bi-color variety with light lavender and burgundy blooms that produces very few seed pods.

·      Lucretia Hamilton: A smaller, more refined variety with deep red-purple flowers.

Pests and Diseases

Generally pest-free, though you might occasionally see aphids or spider mites. The most significant threat is root rot caused by overwatering or poor drainage. Ensure the soil stays primarily dry between waterings once the tree is established.