x Chiltalpa

x Chitalpa

( kye - TAL - puh )

At-A-Glance Information

This hybrid deciduous small tree needs full sun and little to moderate amounts of water for best performance. It produces flowers that will attract hummingbirds to the garden, and rapidly reaches 20-30 feet tall at maturity. They can take between 10 and 20 years to reach their full size. Flowers bloom in clusters in pink, white or mauve and blossom from late spring through fall. These trees will frequently drop spent flowers and leaves in the summer, so they can be a bit messy to clean up after. Use these drought-resistant trees as street trees, specimens, patio trees, hedge plants or as parking lot trees.

x Chitalpa varieties and cultivars

The intrageneric hybrid x Chitalpa is a cross between Desert Willow (Chilopsis linearis) and various Catalpa species (depending on the variety). These trees were created by A. Rusanov (Botanic Garden of the Uzbek Academy of Sciences) of Uzbekistan, and brought to the United States in the late 1970s. x Chitalpa trees grow best in zones 3-24 (to find your zone, click here: Zone Map).

'Morning Cloud'
These trees produce white and pale pink blossoms.

'Pink Dawn'
Flowers are light pink with white-yellow throats.

'Summer Bells Minsum'
A slightly smaller tree with clusters of fragrant, pink-mauve and pale yellow flowers.

Caring for x chitalpa

These popular hybrid trees prefer full sun exposure, needing at least 6 hours of direct sun each day for the best flowering and foliage growth. Avoid planting them in shade, as this can lead to leggy growth and less flowering. Ensure that soil is very well-draining before installing. These trees can tolerate a wide variety of soil types, including sand, loam, and clay, but absolutely cannot have any standing water around their root systems, which quickly leads to root rot. Soil pH should be in the range of 6.0 and 8.0 (slightly acidic to slightly alkaline). Apply a layer of mulch 2-3 inches thick around the base of the tree after installation to suppress weed growth, maintain soil moisture, and regulate soil temperatures. Water young or newly installed trees regularly during the first few seasons so that the tree builds a strong root system. At maturity, Chitalpas are drought-tolerant superstars, able to survive on precipitation alone. To avoid lasting damage, provide infrequent deep waterings during long periods of drought and high temperatures.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Pruning is simple for these trees, and they bounce back well. In late winter or early springtime before new growth pushes out for the year, prune to shape and remove crossing, diseased, damaged or dead branches. These trees grow quickly, and gardeners may wish to prune for size as well from time to time. Remove spent flowers to encourage more blooms in the same year. These trees typically form broad, spreading canopies that make them great shade trees for small spaces. These trees are considered long-lived, and can persist in the landscape for 40-150 years before needing to be replaced.

Propagation

Chitalpa hybrid trees are sterile and do not produce fruits, so they must be propagated asexually. To propagate your tree, follow the instructions below:

Propagating x Chitalpa by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Strip one or more 4- to 7-inch greenwood portion(s) of the end of a non-blooming branch, leaving a messy 'heel' of bark and tissue at the base of the cutting. This is where roots will form. Strip leaves off of the bottom 2/3 of the cutting. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.