The Arizona Cypress, scientifically known as Hesperocyparis arizonica, is a species of tree native to the southwestern United States and northern Mexico. This evergreen tree belongs to the Cupressaceae family.
The tiny leaves of an Arizona cypress tree look like scales and come in different shades of green in different varieties including gray-green and blue-green. The Arizona cypress is monoecious and both the male and female flowers are little, yellowish-green, and found at the tips of the branches.
The history of the Arizona Cypress can be traced back to its natural distribution, which includes the states of Arizona, New Mexico, Texas, and northern Mexico. This tree thrives in arid environments and can be found in the upper Sonoran life zone, as well as the arid transition zones.
One of the earliest recorded mentions of the Arizona Cypress comes from the work of Edward Lee Greene, who in 1882 named the tree Cupressus arizonica. However, this classification was later disputed by Maxwell T. Masters, who in 1896 suggested that it should be considered a subspecies of Cupressus benthamii with the variety name of arizonica.
Indigenous peoples of the southwestern United States, such as the Apache, Navajo, and Pueblo tribes, historically used parts of the Arizona Cypress for many purposes. They often used the wood for construction, crafting tools and implements, and in traditional ceremonies. Other than its natural history, the Arizona Cypress has also been featured in works of art and literature, including the poem “Windows” by John Kinsella.
The Arizona Cypress is an evergreen tree with a conical shape, meaning it has a broad base that tapers towards the top, forming a pyramid-like silhouette. The tree’s branches are slightly ascending, and its foliage consists of scale-like leaves that are arranged in opposite pairs along the branches. The overall shape of the tree is symmetrical.
Arizona cypress is found mainly in northern Mexico in the states of Chihuahua, Coahuila, Durango, Tumaulipas and Zacatecas. It is also found in small areas of the southwestern United States in the southern parts of Arizona, New Mexico, and Texas. In the US it is found between 1000 and 1500 meters in elevation while in Mexico it reaches as high as 2200 meters in some forests.
In the wild, the species is often found in small, scattered populations, not necessarily in large forests. An example occurrence is within the Sierra Juárez and San Pedro Mártir pine–oak forests of Mexico, where it is found along with canyon live oak and California fan palm.
Characteristics of Arizona Cypress
- Size: The tree grows at a moderate pace, adding 1 to 2 feet per year and topping out at between 40 and 50 feet.
- USDA Hardiness Zone: Thrives in USDA hardiness zones 7 to 9. It is well-suited to the warm, dry climates of the American Southwest and Mexico.
- Branches: The tree has a conical shape with branches that are slightly ascending. The branches are covered with scale-like leaves that are gray-green to blue-green in color.
- Growth rate: It is a fast-growing tree, adding 1 to 2 feet per year and reaching a mature height of 40 to 50 feet.
- Lifespan: The lifespan can vary, but it typically lives for 50 to 150 years.
- Cones: The tree produces small, round cones that are 0.8 to 1.2 inches in diameter. The cones are green when young and turn brown as they mature. They usually take two years to mature and release their seeds.
- Bark: The bark is gray to reddish-brown and has a scaly texture.
- Foliage: The foliage consists of small, scale-like leaves that are arranged in opposite pairs along the branches. The leaves are gray-green to blue-green in color and are aromatic when crushed.
- Drought tolerance: It is highly drought-tolerant and can withstand long periods of dry conditions once it is established.
- Salt tolerance: The tree is also moderately salt-tolerant, making it suitable for coastal areas.
- Soil requirements: It can grow in a wide range of soil types, including sandy, loamy, and clay soils. It prefers well-drained soils but can tolerate some degree of soil alkalinity and salinity.
- Wildlife value: The tree provides habitat and food for various wildlife species, including birds and small mammals.
- Pest and disease resistance: The tree is relatively pest-resistant, but it can be susceptible to bagworm infestations and cypress bark beetles. Proper care and maintenance can help prevent these issues.
- Root type: The Arizona Cypress has a deep taproot system. The taproot can grow quite deep, reaching depths of up to 20 feet (6 meters) or more.
- Root growth: The root system of the Arizona Cypress grows rapidly during the first few years after planting, as the tree establishes itself in its new environment. Once established, the root system continues to grow and develop, providing a strong foundation for the tree’s overall health and growth.
Cultivars of Arizona Cypress
| ‘Compacta’ | Dwarf variety with compact growth habit |
| ‘Oblonga’ | Narrow, columnar form with dense foliage |
| ‘Watersii’ | Upright, pyramidal form with blue-green foliage |
| ‘Glauca’ | Silvery-gray foliage coloration |
| ‘Verhalenii’ | Bright grayish-blue foliage coloration |
| ‘Gareei’ | Silver-blue foliage coloration |
| ‘Blue Ice’ | Compact, globe-shaped form with blue foliage |
| ‘Raywood Weeping’ | Weeping form with pendulous branches |
| ‘Fastigiata’ | Upright, columnar form with dense foliage |
| ‘Variegata’ | Foliage with variegated patterns |
| ‘Blue Sapphire’ | Columnar cultivar with a silvery-blue color and a dense, pyramidal growth habit. |
| ‘Aurea’ | Golden-yellow foliage coloration |
How to use Arizona Cypress in the landscape
- Privacy screen: It is good for creating a natural privacy screen or windbreak. Plant several trees in a row to create a living wall that will provide privacy and protection from the elements.
- Specimen tree: With its striking blue-green foliage and pyramidal shape, it can work well as a focal point in any landscape. Plant it in a prominent location where it can be admired from all angles, and consider using uplighting to highlight its unique form at night.
- Xeriscaping: It is well-suited to xeriscaping, a type of landscaping that uses water-wise plants and design principles to minimize water usage. Plant it alongside other drought-tolerant plants such as cacti, succulents, and native grasses to create a low-maintenance, water-wise landscape.
- Wildlife habitat: Its dense foliage offers shelter and nesting sites, while its cones provide food for birds and other wildlife. Plant it in a natural area of your landscape to support local wildlife populations.
- Christmas tree: The Arizona Cypress’s symmetrical shape and dense foliage works well for a living Christmas tree. Plant it in a large container and bring it indoors during the holiday season, or decorate it in place with lights and ornaments. After the holidays, plant it in your landscape to enjoy for years to come.
How to Grow Arizona Cypress From Seed
Blue-ice Arizona cypress
Arizona cypress cones remain closed and on the tree for multiple years, and need treatment to open. Seeds need cold treatment to germinate.
- Select brown cones for harvest rather than green ones or old-looking gray ones. Clip them from the branch with the pruning shears.
- Put the cones in a shaded area where it is warm and dry and protected from seed-eating animals. Allow the cones to dry until the scales separate and the seeds fall out. Alternatively, drop the collected cones in boiling water for 30 to 60 seconds, remove them with tongs and put them on paper towels to dry and open to release the seeds.
- Collect the seeds — there will be between 48 and 112 per cone — and put them in a paper envelope until you are ready to plant them.
- Find a clean bowl, cup or other container of a size that the number of seeds you have will make a single layer in the bottom of the container. Put the seeds in the container and add at least 8 ounces of water. Stir the seeds with a clean spoon to moisten them thoroughly. Alternatively, use a 0.1 percent citric acid solution for soaking to give a 5 percent increase in germination rate. Soak the seeds for 24 hours.
- Remove the seeds from the water and put them on moist paper towels. Fold the paper towel around the seeds and place the towel in a reclosable plastic bag. Put the plastic bag in the refrigerator crisper drawer for 30 days.
How to prune the Arizona Cypress
- Timing: The best time to prune an Arizona Cypress tree is during late winter or early spring, when the tree is dormant. Avoid pruning during the summer, as it can cause stress to the tree and make it more susceptible to pests and diseases.
- Tools: Use sharp, clean pruning tools to make clean cuts and reduce the risk of infection. Tools you may need include hand pruners, loppers, and a pruning saw.
- Assess the tree: Before you start pruning, assess the tree’s overall health and structure. Identify any dead, damaged, or diseased branches that need to be removed. Also, look for branches that are crossing or rubbing against each other, as these can cause damage to the tree over time.
- Remove dead, damaged, and diseased branches: Start by removing any dead, damaged, or diseased branches. Cut these branches back to the point where they intersect with a healthy branch or the trunk. Make the cut at a 45-degree angle, just above the branch collar, which is the slightly swollen area where the branch meets the trunk.
- Thin out the canopy: Thinning the canopy of the Arizona Cypress tree can help improve air circulation and light penetration, which can reduce the risk of disease and promote healthy growth. To thin the canopy, selectively remove branches throughout the tree, focusing on those that are crossing or rubbing against each other. Make the cuts just above a lateral branch or bud to encourage new growth.
- Shaping: If you want to shape the tree, do so by selectively removing branches that are growing in undesirable directions. Keep in mind that the Arizona Cypress tree naturally grows in a conical shape, so try to maintain this shape as you prune.
- Avoid over-pruning: It’s important not to over-prune an Arizona Cypress tree, as this can cause stress and damage to the tree. A good rule of thumb is to remove no more than 25% of the tree’s canopy in a single pruning session.
What Shrubs and Trees Go Well With Arizona cypress?
Shrubs
- Manzanita (Arctostaphylos spp.): These evergreen shrubs feature bark, small urn-shaped flowers, and often have a similar drought-tolerant nature to Arizona cypress. They complement the cypress’s rugged appearance.
- Yucca (Yucca spp.): With their spiky foliage and architectural form, yuccas can provide a good contrast to the texture of Arizona cypress. They thrive in similar arid conditions.
- Agave (Agave spp.): Like yuccas, agaves offer a bold, sculptural presence in the landscape. Their structural foliage and drought tolerance make them excellent companions for Arizona cypress.
- Texas Sage (Leucophyllum frutescens): A drought-tolerant shrub, Texas sage is well-suited to the same hot, dry conditions as the Arizona cypress. It has silvery-green foliage and produces vibrant purple or pink flowers in response to rainfall or high humidity.
- Texas Ranger (Leucophyllum spp.): These shrubs feature silvery-gray foliage and produce showy purple flowers after rainfall, this can create a beautiful contrast with the Arizona cypress.
- Lavender (Lavandula spp.): Its low water requirements make it a suitable companion for drought-tolerant plants like Arizona cypress.
Trees
- Pinyon Pine (Pinus edulis): This pine tree complements well the Arizona cypress with its rugged appearance and drought tolerance. Both species are native to arid regions of the American Southwest.
- Juniper (Juniperus spp.): With their blue-green foliage and interesting growth habits, junipers provide visual interest and texture in the landscape. They are well-suited to the same dry, rocky soils as Arizona cypress.
- Mexican Blue Oak (Quercus oblongifolia): This oak species features blue-green foliage and a compact, rounded form. It pairs well with Arizona cypress in landscapes designed for water conservation.
- Desert Willow (Chilopsis linearis): This deciduous tree or large shrub has a similar drought tolerance to the Arizona cypress and produces beautiful, trumpet-shaped flowers in shades of pink, purple, and white.
- Apache Plume (Fallugia paradoxa): This native shrub/tree features attractive white flowers and feathery seed heads, providing seasonal interest and texture in the landscape. It grows well alongside Arizona cypress in arid environments.
- Creosote Bush (Larrea tridentata): This shrub is native to the southwestern United States and northern Mexico and is well-adapted to arid environments. It has small, yellow flowers and a unique, resinous fragrance.
- California Pepper Tree (Schinus molle): This evergreen tree is native to the southwestern United States and northern Mexico and has a similar drought tolerance to the Arizona cypress. It has a spreading canopy and produces clusters of small, pink or white flowers followed by reddish-brown berries.