How to Grow and Care for Arizona Cypress

Arizona cypress (Cupressus arizonica) is an evergreen conifer that is native to the southwestern region of North America. This tree is an excellent choice for inclusion in a xeriscape and other desert landscaping, because it has low water needs once the root system is established.

With its deep roots, Arizona cypress serves well as a windbreak and for erosion control. It can also be grown as a cut or a living Christmas tree. The tree grows at a moderate to fast pace, adding 1 to 2 feet per year and topping out between 40 and 50 feet.

The tiny leaves of an Arizona cypress tree look like scales and come in different shades of green including gray-green and blue-green. Older trees have a rough bark that scales off to show an innerbarkwith changing color from tan to plum to red.

Arizona Cypress Care

Here are the main care requirements for growing Arizona cypress:

• Plant it in a location with full sun and well-drained soil.
• Give it at least 1 inch of water per month, preferably more, and water deeply.
• Avoid planting it in a humid climate.
• Do not fertilize the tree.
• Prune minimally in the late winter to remove dead wood.

Light

The tree needs a site that provides full sun for plenty of direct light.

Soil

Arizona cypress trees are not particular about soil pH and grow in acidic, neutral, or alkaline soil. They also tolerate clay, loamy, or sandy soils. However, the soil should be well-drained.

Water

While the tree has low water needs of10 to 12 inches of water annually, a monthly deep watering encourages deep rooting and helps the tree thrive.

Temperature and Humidity

The tree is winter-hardy in USDA zones 7-9. It is well adapted to the hot and dry conditions in its native habitats in the American Southwest and Mexico. In areas of high humidity, Arizona cypress is more prone to disease.

Fertilizer

Unless the soil has specific nutrient deficiencies (which only a detailed soil test can reveal), this tree should not be fertilized. Nitrogen can potentially causes damage.

Types of Arizona Cypress

There are five varieties of Arizona cypress: C. arizonica var. arizonica, C. arizonica var. glabra, C. arizonica var. montana, C. arizonica var. nevadensis, and C. arizonica var. stephensonii, which some botanists identify as separate species.Popular cultivars of Arizona cypress include:

• ‘Blue Ice’ is a cultivar with aromatic blue-gray foliage and a smooth, flaking reddish bark. It grows 25 to 35 feet tall and 12 to 15 feet wide.
• ‘Carolina Sapphire’ is a very fast-growing cultivar with lacy silvery-blue foliage. It establishes quickly, reaching 25 to 35 feet in height and 12 to 15 feet in width.
• 'Blue Pyramid’ has sweet-scented powder-blue foliage and a reddish bark. It responds well to shearing, so it is suitable for a hedge. It grows 25 feet tall and 15 feet wide, adding 15 inches of growth per year.
• 'Silver Smoke' is the Arizona cypress cultivar with the brightest foliage. The grey foliage produces the illusion of smoke against the reddish brown, peeling bark. It reaches 20 to 30 feet in height and 8 to 10 feet in width when mature.

Pruning

The tree has a natural classic “Christmas-tree” pyramidal shape and requires no pruning other than to remove dead, damaged, or diseased wood. The best time to prune is in late winter or early spring just before new growth starts.

If you wish to prune the tree as a hedge or privacy shield, be careful not to remove any young shoots, as this could lead to bare spots. Use clean, sharp pruning shears.

Propagating Arizona Cypress

Arizona cypress can be propagated from cuttings. Here's how it's done:

1. Using sharp pruners, cut a 4- to 6-inch green stem just below a node.
2. Remove the bottom few leaves (needles).
3. Dip the stem in water then in rooting hormone.
4. Fill a 4-inch container with moist potting mix. Slide the cutting about 2 inches into the soil.
5. Place the pot in a warm location but out of direct sunlight, and keep the potting mix moist but not soggy.
6. After the cutting has rooted (test by gently tugging on it), transplant it into a larger pot. For the best chance of survival, wait until the seedling has developed a strong root system before planting it in the landscape.
   

How to Grow Arizona Cypress From Seed

It is possible to propagate Arizona cypress from seed, but the process requires some effort and lots of patience.

1. Cut this year's brown cones from the tree and place them in a warm, dry, shaded area. Be sure they are protected from squirrels and other seed eaters.
   
2. Allow the cones to dry out until they "open" and their seeds begin to drop out.
   
3. Sprinkle seeds in a single layer in the bottom of a container, cover with water, and soak for 24 hours.
   
4. Wrap the soaked seeds in moist paper towels and seal them in a plastic bag. Refrigerate the seeds for 30 days for stratification.
   
5. After a month of refrigeration, plant the seeds in small nursery pots with a soilless potting mix. Press one seed about 1/4 inch deep in each pot and cover with a thin layer of packed potting mix.
   
6. Water pots thoroughly, keeping them moist but not soggy, in a location that receives indirect light and a temperature around 72°F.
7. Germination should occur one to two months after planting. Keep the seedlings in a greenhouse for the first winter, then transfer them into the ground the following spring.

Cultivar Seeds?

Keep in mind that Arizona cypress seeds from cultivars won’t produce trees true to the parent.

Potting and Repotting Arizona Cypress

Due to its extensive root system and large size, Arizona cypress is not suitable to be grown in containers. The only exceptions are live Christmas trees. After the holidays, you should plant them in the landscape as soon as possible.

Common Pests & Plant Diseases

Arizona cypress is susceptible to several pests and diseases. Pests include bagworms, which will cause defoliation as these larvae chew their way through the leaves, and cypress bark beetles, which can bore holes into the trunk and risk killing the tree.

Additionally, mistletoes are parasitic shrubs that send roots out into the branches of the tree and steal nutrients. You should prune out affected branches when the mistletoe first forms if possible to keep it from growing and spreading.

Common Problems With Arizona Cypress

Problems with Arizona cypress are generally easy to recognize and occur as a result of improper care or environmental conditions. A few of the common issues owners might encounter include the following:

Galls

Gymnosporangium rusts occur when fungi invade. It leads to problems like galls and witches' brooms. These rusts are usually not too problematic except in rainy years.

Yellow or Brown Needles

Phomopsis blight will cause new growth to turn yellow and then brown as it dies. Make sure your soil offers good drainage as too much moisture often makes the problem worse.

Stem Cankers

Stem cankers should be pruned out as soon as you notice them help maintain the overall health of the tree.

From: thespruce