How to Grow Western Juniper Trees

Close up of western pine cones and needles.

 

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“Give me land, lots of land, and the starry skies above - Don't fence me in”, could be the theme song of the Western Juniper.  

Juniperus occidentalis takes its botanical name from the word occidental, meaning a native or inhabitant of the west. The juniper species, like the singer of the song, is currently seeking to expand its native range.  As humans spread and develop housing, ranching or commercial properties into areas that were once prime ecosystems for the western juniper, the tree has spread elsewhere. This has made the once-great tree somewhat of a nuisance in places that call for forest management. 

Unless you plan to plant a large stand of western junipers, do not let people dissuade you from planting this beautiful native in your own landscape. Be warned, though, that this tree is extremely slow-growing and does not transplant well after it is established. Planning is a must when considering it for your garden.

Western Junipers are conifers which grows to an average of 50 feet with exceptional trees growing to heights as tall as 80 feet. The leaves on mature plants look like scales but are tightly closed needles. The juvenile leaves are needle-like and about one-quarter inch long. The cones on female western junipers are often mistaken for berries. They have blue fleshy pulp that is often covered in a white bloom.

These cones are eaten by wildlife of all sorts, but, if they survive to ripen after two years, they will release their seeds.

Besides providing a meal for the native fauna, the cones, leaves and wood of the western juniper have many uses in medicinal, ritual, craft, and culinary arts, and have been used for these purposes for thousands of years.

The oldest known western juniper in the world is the Bennett juniper in the Stanislaus National Forest of California at 3,000 years old. These trees will last a long time if you plan and care for them properly.

Botanical Name Juniperus  occidentalis
Common Name  Western Juniper
Plant Type Tree, Shrub
Mature Size 12 to 50 feet
Sun Exposure Full Sun to Part Shade
Soil Type Sandy, Gravelly, Loose Rock
Soil pH Neutral but can tolerate very alkaline soils
Bloom Time No Bloom
Flower Color No flower but shows blue to purple berry like cones.
Hardiness Zones 5-9
Native Range West to Pacific Northwest United States
Toxicity No

Western Juniper Tree Care

When growing the western juniper, you will face a few hurdles. Firstly, these trees can be difficult to find in garden centers or nurseries. As mentioned above, it is getting a reputation as one of those odd plants that is both native and invasive at the same time. If you can find one and are planning on planting it in a controlled environment, do not let the “weediness” deter you from growing this iconic tree. 

Secondly, this is an extremely slow-growing tree. For the first ten years or so, the tree’s growth will mostly be in the form of sending a tap root downward. Next, they will send out lateral roots along the surface that may be five times the height of the young tree. Finally, at about 15 years the tree will get a growth spurt and start rapidly growing up, as much as six inches a year, to shape into its conical form. The western juniper is truly an exercise in patience.  

With those considerations in mind, consider your location and plan the home of your western juniper. It will be calling its space home for a very long time. Think about utilities and infrastructure that roots may need to contend with, not just now, but up to two decades in the future.

Remove the tree from its burlap or container (unless you have gotten bareroot) and set it into a hole twice as wide as your tree’s root ball, or container, and just as deep. Make sure to keep it in an upright position as you fill the hole and compress the soil. Lightly mulch to a depth of three inches to the dripline of the tree, making sure that no mulch touches the trunk of the tree itself. If your tree is in a windy spot, consider staking it to ensure that it remains upright.

Light

The western juniper prefers full sun but will handle part shade. Like all junipers, it is adaptable but will not thrive in a shaded environment.

Soil

Loose inorganic soil with neutral pH is best for the western juniper. Adding vermiculite, perlite or a pumice mixture is perfect if you are looking to amend your soil to give it texture to help your juniper thrive.

Water

The western juniper will find water with its immense root system but will require more frequent watering when young. It is a drought-tolerant species, as are most plants in the genus Juniperus.

Temperature and Humidity

This plant prefers warm dry temperatures, but it is cold hardy to -20 degrees Fahrenheit. 

Fertilizer

The western juniper does not require feeding

Is the Western Juniper Toxic?

The western juniper is not toxic and is the most common juniper used in making domestic gin.

Potting and Repotting Western Juniper

The western juniper is often used in the art of making bonsai. Once again, an issue is finding a specimen in the nursery trade. A solution is finding seedlings on private land that you have gained permission to use. The young seedlings are still at a point that can be transplanted and will allow you to harvest multiple plants if you are lucky.

Always remember to get the permission of the landowner and never take from public land. Plant poaching is illegal. 

Once you find a specimen you like, transplant it to a pot with bonsai soil, which consists of inorganics such as pumice, vermiculite, and crushed lava. Occasionally, pine bark is also included. After some time, you can repot to a larger container by removing the soil from the roots and trimming then shaping the tree into your very own western juniper bonsai.