The juniper tree is a pleasingly versatile plant. An evergreen, coniferous tree, the scaly foliage of the juniper helps to make it a distinctive addition to the garden. The plants dense foliage remains thick and green from winter until high summer, providing year round greenery and interest.
Most evergreen cultivars enjoy prickly needle-like growth. This flattens and becomes scaly as the plant matures. The foliage can also change color from shades of green to blues, silver and even bronze in the fall. During the spring the plants produce insignificant yellow or green flowers.
Ideal for a sunny spot in your garden, this an ideal specimen plant. You can also plant a number of trees to create an upright, evergreen hedge. These popular ornamental plants provide interest throughout the year. If you want to add a juniper tree to your garden, this is your complete guide.
Stately and versatile, these specimens come in a range of sizes and can be planted in a multitude of different conditions.
Beware, the sap of the plant is combustible. This means that they are a poor choice in areas that have a high fire fisk. Alternative broadleaf evergreens include rhododendrons, boxwood and Oregon grape.
Different Varieties of Juniper Tree
A member of the cypress family, these plants are hardy in USDA Zones 2 to 10 depending on the variety. There are 13 species that are considered native to North America.
Depending on the variety, junipers can achieve a height of 6 ft to 130 ft and spread of 1 ft to 25 ft. They can be upright, spreading and bushy or have a weeping growth habit. Some can even be used to provide ground cover and are ideal for preventing soil erosion. The range of different varieties of juniper tree currently available means that you are sure to find at least one species suitable for your garden and growing situation.
Different types of juniper include:
- Small cultivars, these achieve a height of 1 to 1.5 ft. They are best used for ground cover, edging, rock gardens and containers. They are also an ideal choice if you want to combat soil erosion.
- Dwarf cultivars, these can reach up to 4 ft in height. Ideal foundation plants, they can be planted close to ponds or cultivated as bonsai specimens.
- Small juniper tree plants have a mature height of around 6 ft. Like dwarf cultivars they are ideal foundation plants.
- Large specimens can have a mature height of over 60 ft. These are best used as statement plants in large gardens or in woodland and forest planting schemes.
Don’t be too put off by the classification of the plant. Some varieties that are classified as shrubs are really small trees. For example, Pfitzer juniper (J. chinensis Pfitzerana) is a cultivated shrub which averages a height of 5 ft and a spread of 10 ft. While it is classed as a shrub, some growers consider it to be a tree. Similarly, Hetz Chinese (J. chinensis Hetzii) reaches 15 ft in ideal conditions but can still be classified as a shrub. In short, don’t be put off by the description of a plant. As long as it meets your growing conditions and purposes then it is the ideal choice for you.
Coming in many different sizes, you can plant a single specimen for a statement plant or a line of specimens to create evergreen hedging.
Garden stores and plant nurseries usually sell young saplings or juniper tree plants. These are ready for planting straight out into your garden.
How to Plant
Selecting the right location helps to make caring for a juniper tree a lot easier. Certain varieties may have specific requirements so check the plant information before planting.
Plant your specimen in a full sun spot. Ideal the chosen areas should receive 6 to 8 hours of sunlight every day. While some varieties may require a little afternoon shade, avoid planting in overly shady or dark positions. In general, these plants do well in hot weather and warm positions.
The soil should be well draining. Juniper struggles in wet or boggy soil. If your soil is particularly heavy or poor there are a number of ways to improve it before planting. Preferring a slightly acidic soil, unlike many plants they also tolerate poor and dry soils well.
These surprisingly hardy plants do well in poor or arid soil conditions.
When selecting your planting position, remember to take into account the size that the plant will be when fully mature. Juniper has a quick growth habit and can smother other plants if planted too closely together. You should also take into account larger structures such as fences and overhead objects such as power cables.
The juniper tree is best planted either in early spring or fall. The soil should be warm and not cold or frozen. Plant during mild weather to avoid heat or cold stress.
Before planting work in organic matter, such as compost, to enrich and loosen the soil.
With a shovel, dig a hole 2 to 3 times wider than the root ball. When placed in the hole the top of the root ball should sit slightly below soil level.
When you are happy with the size of the hole, remove the plant from its pot. Gently tease out the roots. This helps them to spread evenly when planted in the soil. If the root system is pot bound you can also make slits in it to help free the roots.
Place the sapling in the hole. The plant should sit in the center of the hole, as upright as possible. After positioning, fill the hole with loose soil or fresh potting soil. As you fill the hole, periodically tamp down the soil to remove any air pockets. Don’t cover the top of the root ball.
Install a stake to keep the specimen upright. This is particularly important if you are planting in an exposed or windy position. The Kradl Tree Staking Kit is an easy to use, durable solution that helps to ensure your plants have a good, upright growth habit.
Use a garden hose to evenly soak the soil around the sapling. Continue to water a couple of times a week until the plant is established and new growth is visible.
If you are planting more than one specimen, make sure that they are spaced out correctly. This helps to promote air circulation and reduces the chances of a fungal disease affecting your plants. While young plants may look too far away from each other remember that they have a quick growth habit and will quickly fill the space.
Planting in Pots
Small or dwarf cultivars can be cultivated in containers. Ensure that your pot is large enough to comfortably hold the mature plant. Repotting large specimens can be difficult.
Before planting place a thick layer of gravel on the bottom of the pot. Next, add a thin layer of rich, well draining potting soil. Center the sapling in the middle of the pot. When placed in the pot the top of the root system should sit just below the top of the pot. You may need to add or remove soil to get the level right.
When you are happy with the position of the plant, carefully fill the pot with more potting soil. Be careful not to overly sink or disturb the position of the juniper tree. Firm down the soil gently. Water well.
Smaller specimens can be grown in pots or even as a bonsai plant.
How to Care for a Juniper Tree
Following planting, continue to water the soil evenly for the first few weeks. This helps the root system to develop and establish itself. When new growth is visible the plant can be considered established. At this point you can gradually reduce watering.
Applying a layer of mulch around the base of the plant helps the soil to conserve moisture. It also helps to suppress weed growth and keeps the soil neat. When applying the mulch, don’t allow it to contact the trunk of the sapling.
When to Water
Once established, juniper requires no additional watering unless you are going through an extreme drought or prolonged spell of hot weather. In this case you can water the soil around the plant lightly.
A drought tolerant plant, the juniper tree is more likely to suffer from overwatering than a lack of water.
How to Fertilize
If planted in rich soil these plants don’t require additional fertilizing. A soil test kit can tell you more about the quality and nutritional value of your soil.
In early spring add an all purpose slow release fertilizer in early spring. A granular fertilizer should be evenly spread over the entire root zone. Water the fertilizer in well. You can also use a liquid fertilizer to enrich your plants.
Do I Need to Prune my Plant?
A low maintenance plant, the juniper tree doesn’t require lots of pruning. Most cultivars naturally keep their shape.
In early spring, use a pruner or hedge trimmer to cut away dead branches and any errant growth. If the plant does require light shaping this is also best done in early spring.
Prune young plants as lightly as possible to keep them healthy and compact. Over pruning can be problematic, potentially causing uneven or stunted growth.
When pruning older plants, take care not to cut the branches back too far past the living growth and into the dead center of the plant. Foliage rarely regenerates past this point. Over pruning can result in permanent bare patches.
Common Problems and How to Solve Them
If planted correctly in a favorable condition, the juniper tree is a largely trouble free plant.
Planting in wet soil, or overwatering, can cause either root rot or tip blight. Planting in overly shady positions or too close to other plants so that air struggles to circulate can also cause disease.
Avoid planting close to apple trees. These specimens are prone to cedar apple rust. This is a nasty fungus that can destroy apple trees, hawthorns, crabapples and quince trees.
Phomopsis blight can also affect specimens. Unlikely to kill older, established plants, phomopsis blight can cause branch tips to brown and become unsightly. The issue can be controlled by regularly spraying new growth with a fungicide during the growing season.
These plants can be susceptible to infestations from pests such as spider mites, juniper twig girdler, needle miner, bagworm, scale juniper, bark beetle and sawfly. Regularly check your trees for signs of infestations. Most infestations can be treated with an application of homemade insecticidal soap.
The juniper tree is one of many larger plants that deers tend to leave alone. This is because they dislike the bitter taste and sharp needles.
A low maintenance plant, deer and larger animals tend to leave the plants alone because they dislike the plant’s distinctive foliage.
Warning berries, stems and needles can all be mildly toxic to cats and dogs if consumed. While rarely fatal it can cause vomiting, diarrhea and kidney issues. If your pet consumes any part of the plant and you are concerned, consult your vet immediately.
Providing low maintenance, hassle free greenery throughout the year, growing a juniper tree is pleasingly easy. Why not add one to your garden today?