If you’re looking for an evergreen groundcover to incorporate into your backyard’s landscape design, look no further than the Japanese juniper. This wonderfully low-maintenance plant can be used to create a lush, carpet-like mass of foliage that looks great all year long. Japanese junipers are also one the most popular junipers to grow as bonsai trees. Their slow growth and ability to withstand severe pruning make them a perfect bonsai species. You can use them to liven up your backyard patio or front yard porch. There are also dwarf Japanese juniper cultivars like ‘Nana’ which can be used in compact spaces where they won’t take over. Dwarf species are those which grow less than 6 inches per year.
Japanese garden junipers are slow growing and lack serious pest and disease issues. They are more heat-tolerant than many other juniper species. You can plant them as far South as USDA hardiness zone 9 without issue. There are three cultivars of Japanese juniper that are widely available. Though they are all low-growing plants, they differ slightly in their growth habits and their foliage coloration. Choose one that speaks to you and ties in with your yard’s current landscape design. Whether you use it to line a walkway in the front yard or on slopes for erosion control in the backyard, you’ll love how Japanese junipers add year-round beauty and interest to your landscaping.
Growth and Care Guidelines
Before you get started planting Japanese junipers in your landscape, you’ll want to make sure your yard has the right conditions. The table below describes what these wonderful, low-lying shrubs need to grow their best. Make sure you plant them in well draining soil and pick a spot in your yard that gets plenty of sunlight.
| Soil Type | well-drained |
| Soil pH | 6.0 – 8.0 |
| Water requirements | Low to moderate, drought-tolerant once established |
| Sun Exposure | Full sun |
| Temperature | 10 – 90 degrees Fahrenheit |
| USDA Hardiness Zones | 4 – 9 |
| Pruning | Tolerates severe pruning well |
| Pests | Spider mites |
| Diseases | Tip blight |
How To Use Japanese Junipers For Landscaping
Japanese Juniper Bonsai Trees
Japanese junipers can be trained as bonsai trees which you can grow in containers. They’re extremely forgiving when it comes to pruning and slow growing which is ideal for bonsai trees. When growing Japanese juniper bonsais in pots, it’s essential that you plant them in well-draining soil as the roots don’t like soggy soils. You will also want to fertilize your juniper bonsai monthly during spring and summer with a diluted liquid fertilizer to encourage healthy growth.
When pruning your bonsai it is important to know that if you remove all of the foliage from a branch, none will grow back. If you want new growth to continue on a specific branch, you must leave some foliage on the branch because a bare branch won’t sprout new needles. Along with bonsai pruning, you can use wiring to train various branches and to spread out dense foliage. It will take some patience and care to develop a beautiful Japanese juniper bonsai, but the effort is well worth it since these magnificent trees can live for a century or more.
TIP: If your bonsai is yellowing, first make sure you aren’t over or underwatering it. You should let the soil dry between watering but not remain dry for extended periods. Juniper bonsai yellowing can also occur if plants aren’t getting enough humidity. This often is only an issue when juniper bonsais are grown indoors. Indoors you should mist them daily or use a humidifier to ensure they have enough moisture in the air. Lastly, make sure your juniper hasn’t become rootbound. If you see roots growing out of drainage holes or on the surface of the soil, it’s time to repot your juniper bonsai.
Green Mound
Juniperus procumbens ‘Green Mound’, also called Green Mound Japanese Garden Juniper, is a versatile, low-growing cultivar with gorgeous blue-green foliage. It spreads across the landscape, creating a rug-like carpet of evergreen foliage. Though the common name suggests otherwise, ‘Green Mound’ doesn’t mound up at the center as many other groundcover junipers do. It grows to around 1 foot tall and sprawls out to 4 to 6 feet wide. It can be grown in USDA hardiness zones 4 through 9.
While you won’t be able to add height to your backyard landscaping with this variety, there are several other uses for Japanese juniper ‘Green Mound’. As a groundcover, it can be used in mass plantings to help with erosion on surfaces with or without a slope. You can grow it along retention walls where it will cascade down over them, helping to make them more attractive. Its drought tolerance makes the Japanese juniper ‘Green Mound’ the perfect plant for rock gardens. Add it to your front yard flower beds as edging or as a foundation plant around the perimeter of your home.
TIP: As ‘Green Mound’ ages, some of the oldest branches at the center may die back. Since Japanese junipers handle pruning with ease, you can simply trim these branches off to keep ‘Green Mound’ looking healthy and beautiful.
Kishiogima
Juniperus procumbens ‘Kishiogima’ is the most uniquely colored variety of Japanese juniper. It is similar to ‘Nana’ in form and growth, but unlike Nana, its needles change color throughout the seasons adding interest to your landscape design. In summer, the foliage has an array of green tones with highlights of bright yellow throughout. In winter, the yellow foliage fades but the overall plant still bears color variations making it stand out in the drab winter landscape. This slow-growing groundcover has a growth rate of around 4 inches each reach, reaching a height of 1 foot and spread of more than 3 feet. It can be grown successfully in USDA hardiness zones 4 through 9.
‘Kishiogima’ Japanese juniper makes a fantastic ground cover plant you can use in mass plantings on slopes to help with soil erosion. It can be grown in backyard rock gardens or Zen gardens thanks to its tolerance to drought-like conditions. Since it grows slowly, it can also be used as an edging plant along walkways in the front yard or as a patio border planting in the backyard. You can also grow ‘Kishiogima’ as a bonsai in a flower pot and place it on your porch or patio to enhance your decor.
TIP: When using ‘Kishiogima’ as an edging plant, you may need to prune wandering stems every year or two. This will keep your edges looking clean and well-maintained.
Nana
Juniperus procumbens ‘Nana’ also goes by the common name dwarf Japanese garden juniper. Its needles are blue-green when they mature and can take on a slightly purplish hue during cold winters. ‘Nana’ is a dwarf juniper species that grows no more than 1 foot tall in the landscape, spreading to a width of 5 to 6 feet. Its growth form can be impacted by the amount of space it has to grow. In compact spaces, it can mound up, looking more like a shrub, while in open areas it will spread across the landscape. You can grow Japanese juniper ‘Nana’ in USDA hardiness zones 4 through 9.
‘Nana’ has many of the same landscaping uses as other Japanese junipers. It can be grown in mass plantings, as foundation plants, as edging, in rock gardens, and along slopes to help with erosion. While it can cascade down retention walls like ‘Green Mound’ it can also grow upwards over small garden walls and rocks. This makes it a great specimen for rock gardens in the backyard.
Japanese juniper ‘Nana’ is also a very popular bonsai cultivar. You can easily prune it into an enchanting miniature tree. Plant it in a pot that matches your outdoor décor and these whimsical plants will look stunning on the porch in your front yard.
References
Breen, P. (n.d.). Juniperus procumbens ‘Nana’. Landscape Plants, Oregon State University.
Juniperus procumbens. (n.d.). North Carolina Extension Gardener Plant Toolbox, North Carolina State University.
Juniperus procumbens ‘Green Mound’. (n.d.). Missouri Botanical Garden.
Juniper Tip Blights: Phomopsis juniperovora, Kabatina juniperi, or Sclerophoma pythiophila. (2018). Cornell University, Plant Disease Diagnostic Clinic.
