Rocky Mountain juniper (Juniperus scopulorum) is a large needled evergreen found high in the Rocky Mountains from Canada to Texas in dry gravelly and rocky soils. The cultivated variety of the wild type, Juniperus scopulorum 'Wichita Blue', is a much smaller version of the species often used in horticulture as a screening shrub or as a wind break in water-wise gardens. Its pyramidal form and bluish color make it appealing, while its ability to sustain itself for lengths of time without irrigation makes it a popular selection in drought-prone areas. The cultivar is also bred to be dioecious, i.e., male, so it does not flower and does not produce cones which some people consider messy.
The cultivar of this species is famously easy to care for with few pests and diseases to worry about, little if any pruning, and supplemental irrigation only while being established. When looking for an attractive alternative to an old standby such as arborvitae, the 'Wichita Blue' Rocky Mountain juniper is a tree to consider for your next landscaping project.
|Common Name||Rocky Mountain juniper|
|Botanical Name||Juniperus scopulorum 'Wichita Blue'|
|Plant Type||Needled evergreen|
|Mature Size||10 to 15 tall 4 to 6 feet wide.|
|Sun Exposure||Full sun|
|Soil Type||Adaptable to many soils except wet|
|Native Area||Western North America|
Caring for the 'Wichita Blue' Rocky Mountain Juniper
In these days of water consciousness, finding an alternative to ever-thirsty plants is often a priority when designing a landscape. When a person can find a selection that is waterwise and is easy to care for but suffers from a few issues that affect the plant's health, that plant becomes a new go-to favorite.
Juniperus scopulorum 'Wichita Blue' will be many people's favorite conifer hedge because of all those appealing factors. In today’s world, with people’s schedules and our changing viewpoints, easy care and sustainability make a tree like these traits reasons to buy a selection.
To care for the ‘Wichita Blue’, there is very little needed outside the regular care and information you should know about any plant you purchase. Being informed will increase the odds that your plant will have a long, happy, healthy life together.
Planting a ‘Wichita Blue’ juniper in full sun will give it the best chance to thrive and grow at its intended rate and be the tree that is adept at avoiding problems that often plague other conifers that serve the same horticultural purpose. The best bet is to plan accordingly and know the sun exposure that tree will get throughout its lifetime, from a sapling to a mature tree, considering surrounding structures and other plants.
Like the native species, the cultivar is highly adaptable to various soil types and can thrive in poor soils that would normally make other plants suffer. The wild type of the species makes it home in the foothills and slopes of the Rocky Mountains at elevations over 5000 feet. The soil at these elevations is often gravelly, sandy, and coarse stone with low amounts of organics, yet the tree thrives. One limit to the ‘Wichita Blue’ juniper’s adaptability is its lack of tolerance to wet soils. The species and the cultivar demand soil with good drainage.
Once established, Rocky Mountain juniper 'Wichita Blue' can completely rely on natural irrigation. The big phrase that needs to be noticed is once established. Do not plant and forget. The tree will require plenty of supplemental irrigation to get it to a point where it can cope with the driest conditions.
Watering a 'Wichita Blue' to establish it to maturity may take two or three years of weekly watering during its growing season. The usual method of measuring the diameter of the tree’s trunk by caliper and watering ten gallons per inch per week decides how much water is needed. After two or three years, the tree’s roots will be established enough to maintain itself through dry spells without outside assistance.
Temperature and Humidity
An environment that this very adaptable tree does horribly in is a hot, humid climate. If this describes the location of the landscape that is being considered to plant a Rocky Mountain juniper 'Wichita Blue,' another species would be a better option. The geographic location and the specific habitat paint a great picture of what this plant prefers regarding living conditions. Heat can be somewhat tolerated, but a dryer heat must be balanced by a cooler dormant season as in the Rockies. The USDA hardiness zone for the Rocky Mountain juniper 'Wichita Blue' is zones 3-7.
While the Rocky Mountain juniper 'Wichita Blue' is quite used to poor soil in the wild in a landscape setting, it does not need to contend with these adverse conditions. This also does not mean there is a license to fertilize liberally either. During the planting of the tree, introducing some good organic compost into the fill around the tree will give it a boost and help provide some nutrients for the first growing season. As the next spring arrives, it is a good time to test the soil and see if there are any deficiencies and if supplemental feeding is needed. If so, a good fertilizer formulated specifically for conifers is always a great choice. Usually, it will serve the right NPK values your juniper will be hungering for.
Types of 'Wichita Blue' Rocky Mountain Juniper
Juniperus scopulorum 'Wichita Blue' is itself one of many cultivars of the species J. scopulorum. You will not find other types of 'Wichita Blue' as it has been cultivated specifically in the nursery trade as a selection to present certain desirable traits that the wild type of the species might not have or another cultivar might be lacking. In this case, the 'Wichita Blue' Rocky Mountain juniper has been selected to be dioecious (male) for its outstanding blue foliage, higher than normal drought tolerance, upright formal pyramidal shape, freedom from pests and disease, and small growth habit that makes it ideal for small yards or mass plantings. While Juniperus scopulorum is highly drought tolerant, it lacks every other trait and is monoecious, traditionally undesirable to horticulturalists and urban foresters.
'Wichita Blue' Rocky Mountain Juniper Propagation
Propagating the 'Wichita Blue' Rocky Mountain juniper often proves difficult not because establishing viable specimens is rare but because raising plants that carry over the desired pyramidal form is often hit or miss. Propagating prostrate forms of juniper is much easier as the form is less important. The best method to overcome this hurdle is mass propagation, which is often not feasible for a home gardener. If interested in attempting, the propagation method used softwood cutting.
Gather your tools and materials, A sharp, clean knife, a pot with deep drainage holes, and large enough for several cuttings—a stick or pencil. A mix of pre-soaked vermiculite and perlite fills the pot. And rooting hormone gives the development of roots a boost.
Then the steps are the same as you would perform for any other softwood cutting:
- First, take a cutting about 5-7 inches from new growth at the end of a branch that already has somewhat of the desired form you want. This will not guarantee the result but will get you in that direction.
- Remove the foliage from the bottom ⅔ of the cutting and scrape away the bark exposing the fleshy part of the cutting.
- Make a clean cut with your knife at the end of the cutting at a 45° angle.
- With the pencil, poke a hole in the potting mix for the cutting.
- Dip your cutting in your rooting hormone of choice according to the instructions and then place the cutting in the hole in the potting mix and repeat the process for as many cuttings as you wish.
- Keep the potting mix moist and in a cool, indirectly lit area for at least six to nine months to establish roots.
- Once roots have been established, transplant them to individual pots and let roots establish in those pots for at least a year.
Pruning 'Wichita Blue' Rocky Mountain Juniper
Pruning of a 'Wichita Blue' Rocky Mountain juniper should be done sparingly and only to manage form and remove dead or damaged branches. Over pruning or pruning to bare wood can damage or kill the tree. Most conifers will not produce new growth from old the 'Wichita Blue' Rocky Mountain juniper is no exception, so before pruning, proceed with caution and be sure it needs to be done, or consult a certified arborist.
If you do attempt to prune the tree, be sure to have a good sharp pair of pruners and loppers. Prune the tree in the early spring when new growth has appeared and cut in layers trying to mimic the natural pyramid shape of the plant. One way to successfully layer cuts is to hide pruning cuts underneath branches above them. You are again stressing the importance of not over-pruning and considering that under-pruning is always better than over-pruning.
Common Pests and Plant Diseases
One reason Juniperus scopulorum 'Wichita Blue' is gaining traction as a viable replacement for longstanding favorites like the arborvitae is its relative ability to withstand issues that plague other conifer hedges. While not completely without worry, the threats to the 'Wichita Blue' Rocky Mountain juniper are usually hindrances that last a season or aesthetic issues.
The biggest pathogen a juniper will often face is often caused by a fungus and does more damage to fruit nearby fruit trees than the juniper itself. Cedar-apple rust and other rust diseases inhabit junipers as part of their life cycle. Treatment of a copper fungicide is a good solution, but again this is more of a concern for a fruit crop than a juniper.
The biggest pest invader you will find causing issues is the spider mite. This tiny nuisance is easily handled with a powerful spray of water in the easiest cases and some neem oil or horticultural soap in the worst cases. At the very worst, they can do some damage to your tree, but it is noticeable and can be stopped before any permanent damage is done.
How long do 'Wichita Blue' Rocky Mountain juniper live?
These are somewhat short-lived trees, living only 70 years or so.
How fast does a 'Wichita Blue' Rocky Mountain juniper grow?
The tree grows moderately slow at 6 to 12 inches per.
Are the berries safe on 'Wichita Blue' Rocky Mountain juniper safe to eat?
If you have berries on your Rocky Mountain juniper, you don't have a 'Wichita Blue'! All 'Wichita Blue' Rocky Mountain juniper is male and doesn't produce berries, but the good news is the berries on your Rocky Mountain juniper are edible and are often used to flavor teas, stews, and alcoholic beverages.