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Junipers are one of the most easily recognized and popular species used in
bonsai. Juniperus is a genus with over fifty species of evergreen conifers
from all over the world. Very often given near Christmas time as a first
bonsai, juniper are suitable subjects for beginners and advanced bonsai
enthusiasts alike.
Junipers are characterized by two kinds of foliage, scale and needle-like.
Species which feature one type of foliage are better suited to bonsai, as the
tree will be in better harmony with itself, as opposed to tree that features
both needles and scales as juvenile and mature foliage respectively. Juniper
range in colours, from almost blue-greens, deep hunters, and silvery foliage,
some varieties even taking on purple and golden hues in the winter. Junipers
are evergreens, and will not lose their foliage in the autumn, giving them a year-round appeal.
Often erroneously labeled at indoor bonsai by unscrupulous vendors, Juniper are definitely an outdoor bonsai.
Keeping your juniper indoors for more than a day or two for showing will lead to its decline and ultimate death.
Hardiness: Zone 2-8, with winter protection below zone . These trees are frost hardy, and most require periods of
cooler temperatures to survive. Zone specific needs are listed below.
Light: Full Sun. Though smaller trees may need some protection during the hottest parts of the day to keep their
roots from heating up too much.
Soil: Well draining, extra porous mix, more grit than organic matter. They grow in naturally sandy soil and on
rocky hillsides, and will benefit from a very fast draining potting medium.
Watering: They tolerate, and in fact, enjoy, slightly drier conditions than many bonsai, but that said, still never
allow them to dry out completely. Water as needed, when the soil is mostly dry. Do not allow to remain damp or
boggy. Though they prefer a well draining mix, Junipers can consume a surprising amount of water during the
growing season and winter both, and should be checked frequently.
Fertilizer: Use a balanced fertilizer through the growing season. Tapper off in late summer. Use a nitrogen free
fertilizer through the fall. Nothing in winter, though a single dose of a slow release, balanced feed in mid winter
can strengthen spring growth.
Pests and Diseases: Juniper blight, cedar-apple rust, juniper scale and spider mites can all cause problems, though
mites are the most common and easiest to deal with. Also keep an eye out for bagworm caterpillars, juniper
webworm, and juniper tip midge.
Repotting: Every one to two years for younger trees, three to five years for older as needed. Recommended in late
winter, early spring, but can also be done in autumn if need be.
Pruning and Styling: Juniper require constant pinching of new growth throughout the growing season to keep
their foliage compact. Do not use scissors however, as this will cause the tips of the foliage to brown. Grasp the
new shoots (lighter colour and fatter appearance) between the thumb and forefinger of one hand and simply
pulling off the tip with the other. Remove excess shoots and leaves from the base and bottoms of branches to keep
the trunkline and main branches clear. Also foliage hanging from the underside of branches should be removed.
Toward the end of the growing season, extending shoots can be trimmed back to the first small side shoot, to
allow light and air to continue to penetrate into the inner areas of the tree. Pruning can be done at almost anytime
of year, but avoid the hottest months of the summer. Junipers will backbud on old wod, but removal of all foliage
(as in a trunk chop below the lowest living branch) will result in the death of the tree.
Junipers take well to wiring, and though generally wired in winter, can be wired at any time of year. Wiring can
take some time to set however, and subsequent wirings may be needed. Branches up to a quarter of an inch thick
(5mm) may set in as little as a year or two, though some larger, thicker branches may never set, and will always
need to be held in place.
Jin and shari work well with junipers, though carefully follow the life lines in the bark to prevent die-off of higher
branches. Make certain that all living branches are connected to the root system by a line of living bark. Try
working jin or shari in the late summer, so the sound still has time to heal and be lime sulphured.
Propagation: Layering. Cuttings: Soft and hardwood cuttings. As new growth matures in summer, take 4 inch
(10-cm) cuttings from the tip of the stems. Cuttings should have at least three sets of leaves. Can also be taken in
November or December. Use a mixture of half sand/perlite, half peat. Cut the ends of the cutting in a wedge
shape, but be careful not to crush them. Use rooting hormone on the ends if you wish. Make a hole in the soil with
a stick, then insert the cuttings up to a third of the way into the potting medium. Keep moist, but not soggy, and
mist regularly. Keep in partial shade. Old foliage will turn yellow and fall off. When new shoots begin to grow,
you can be sure the cutting has rooted. Juniper cuttings can take a long time to root, so be patient.
Seeds: Do not always breed true to seed, not having the same characteristics of the parent plant. To start seeds
indoors. Remove pulp, pour boiling water over the seed, and let cool down over night. Press seeds into the surface
of moist, peaty soil. Keep cool, below 50F(10C) and fully exposed to light. Seed should germinate within 180 days if
consistently kept cool and moist.
Styles and Forms: Junipers can take well to any style except broom.
Species and Cultivars: J. chinensis "Shimpaku"- one of the most popular species for use in bonsai, characterised by a
red tone to the bark and clouds of hunter green scale foliage. Also known as Sargent's juniper. A natural defense
mechanism in times of stress, in it's natural habitat a shimpaku can limit its foliage mass by allowing entire branches
to die off. Natural deadwood is common on these in the wild where the bark and roots connecting the severed
branch also die off. Will produce dark blue berried with a white coating. Hardy to zone 5.
J. chinensis "San Jose" - San Jose Juniper. Have both scale and needle foliage. Grayish, flaking bark. Vigorous
growers. Hardy to zone 4.
J. chinensis "Torulosa" or "Kaizuka - "Hollywood Juniper" a variant of the Shimpaku. Tree like growth habit. Heat
tolerant. Hardy to zone 5.
J. communis - "Common or Ground Juniper" Extremely hardy. Slow growing with habits ranging from ground
cover, to shrub to small tree. Branches tend to be more brittle than other varieties. Hardy to zone 2.
J. procumbens "Nana" - "Dwarf Japanese Garden Juniper" sharper, scaly foliage that sometimes turns purplish in
winter. Tough species and relatively forgiving. A creeping habit, well suited for semi-cascade and cascading styles.
Do not usually produce berries or cones. Common in most nurseries and DIY stores, a reasonably priced shrub
with potential is easier to come by without spending a fortune. Hardy to zone 4.
J. rigida - Needle juniper. Slightly different, both in foliage and habit from other species of juniper. Also called
"Temple Juniper," this species has very sharp, needle like leaves, clustered in groups of three on slender shoots.
Because the shoots are slender, it can often give the tree an unkempt appearance, so regular pruning is required. At
the base of each needle is a dormant bud, which will usually produce a new shoot after trimming. The more severe
a trimming, the greater number of dormant buds will extend. This can lead to an overcrowded foliage mass
(inviting critters like spider mites). To prevent this from occurring, prune away the ends of older twigs once a
year- the newly growing shoots will grow on to replace the pruned twigs. In time, this process can be repeated as
the foliage mass grows to heavy again. Crowded branches, beside being appealing to pest, will lead to die back
within the inner parts of the tree as light and air cannot reach. Needle junipers also have stiffer, more brittle
branches than Chinese junipers, and more care must be taken when wiring. Needle junipers have a bad reputation
for dying without apparent cause. There is *always* a cause, but the plant's metabolism is so slow it can take
months before it starts to signs that it is in distress, and might already have been dead for some time at that point.
Hardy to zone 6.
J. squamata - Squamata junipers originated in Nepal. Slender, often floppy shoots are densely gathered with soft,
blue-green needles which point forward, almost hugging the shoot. These will extend as they grow, standing more
erect and exposing the dormant bud at the base. Naturally dense growth pattern. Young shoots are delicate, and
easily dislodged during pruning and wiring. They will regrow in time, but treat them with respect to avoid the
extra headache. Slow growing, resistant to Juniper Blight. Hardy to zone 4.
J. ashei - "Ashe Juniper" Native to Texas and parts of central America. Scale foliage. Hardy to zone 7.
J. californica - "California Juniper" Scale foliage. Native to the Mojave Desert, Arizona, Nevada, New Mexico.
Though native to high altitudes, can be grown at low altitudes without difficulty. Hardy to zone 8.
J. virginiana - "Eastern Red Cedar" Not a true cedar. In nature can grow to be 40-50 ft tall. Reddish brown shaggy
bark with deep green scale foliage. Well suited for upright, literati and forest styles. Hardy to zone 2.
J. prostrata - Low ground, spreading habit. Grey-green foliage and flaky bark. Twisted and gnarly in natural form,
well suited for deadwood styles. Hardy to zone 3.
Other Information: Avoid cultivars with the "blue" title in the name (ex. "Blue Star"). These tend to be weaker,
more prone to disease and infestations.
In nature, junipers sometimes allow branches to die off to keep the balance of the tree (demands of the foliage
versus the ability to provide water from the roots) in tact. This can also happen in pot-grown bonsai, and if a
branch dies off for no apparent reason, it may simply be the tree following it's natural inclinations to balance out
it's growth.
bonsai. Juniperus is a genus with over fifty species of evergreen conifers
from all over the world. Very often given near Christmas time as a first
bonsai, juniper are suitable subjects for beginners and advanced bonsai
enthusiasts alike.
Junipers are characterized by two kinds of foliage, scale and needle-like.
Species which feature one type of foliage are better suited to bonsai, as the
tree will be in better harmony with itself, as opposed to tree that features
both needles and scales as juvenile and mature foliage respectively. Juniper
range in colours, from almost blue-greens, deep hunters, and silvery foliage,
some varieties even taking on purple and golden hues in the winter. Junipers
are evergreens, and will not lose their foliage in the autumn, giving them a year-round appeal.
Often erroneously labeled at indoor bonsai by unscrupulous vendors, Juniper are definitely an outdoor bonsai.
Keeping your juniper indoors for more than a day or two for showing will lead to its decline and ultimate death.
Hardiness: Zone 2-8, with winter protection below zone . These trees are frost hardy, and most require periods of
cooler temperatures to survive. Zone specific needs are listed below.
Light: Full Sun. Though smaller trees may need some protection during the hottest parts of the day to keep their
roots from heating up too much.
Soil: Well draining, extra porous mix, more grit than organic matter. They grow in naturally sandy soil and on
rocky hillsides, and will benefit from a very fast draining potting medium.
Watering: They tolerate, and in fact, enjoy, slightly drier conditions than many bonsai, but that said, still never
allow them to dry out completely. Water as needed, when the soil is mostly dry. Do not allow to remain damp or
boggy. Though they prefer a well draining mix, Junipers can consume a surprising amount of water during the
growing season and winter both, and should be checked frequently.
Fertilizer: Use a balanced fertilizer through the growing season. Tapper off in late summer. Use a nitrogen free
fertilizer through the fall. Nothing in winter, though a single dose of a slow release, balanced feed in mid winter
can strengthen spring growth.
Pests and Diseases: Juniper blight, cedar-apple rust, juniper scale and spider mites can all cause problems, though
mites are the most common and easiest to deal with. Also keep an eye out for bagworm caterpillars, juniper
webworm, and juniper tip midge.
Repotting: Every one to two years for younger trees, three to five years for older as needed. Recommended in late
winter, early spring, but can also be done in autumn if need be.
Pruning and Styling: Juniper require constant pinching of new growth throughout the growing season to keep
their foliage compact. Do not use scissors however, as this will cause the tips of the foliage to brown. Grasp the
new shoots (lighter colour and fatter appearance) between the thumb and forefinger of one hand and simply
pulling off the tip with the other. Remove excess shoots and leaves from the base and bottoms of branches to keep
the trunkline and main branches clear. Also foliage hanging from the underside of branches should be removed.
Toward the end of the growing season, extending shoots can be trimmed back to the first small side shoot, to
allow light and air to continue to penetrate into the inner areas of the tree. Pruning can be done at almost anytime
of year, but avoid the hottest months of the summer. Junipers will backbud on old wod, but removal of all foliage
(as in a trunk chop below the lowest living branch) will result in the death of the tree.
Junipers take well to wiring, and though generally wired in winter, can be wired at any time of year. Wiring can
take some time to set however, and subsequent wirings may be needed. Branches up to a quarter of an inch thick
(5mm) may set in as little as a year or two, though some larger, thicker branches may never set, and will always
need to be held in place.
Jin and shari work well with junipers, though carefully follow the life lines in the bark to prevent die-off of higher
branches. Make certain that all living branches are connected to the root system by a line of living bark. Try
working jin or shari in the late summer, so the sound still has time to heal and be lime sulphured.
Propagation: Layering. Cuttings: Soft and hardwood cuttings. As new growth matures in summer, take 4 inch
(10-cm) cuttings from the tip of the stems. Cuttings should have at least three sets of leaves. Can also be taken in
November or December. Use a mixture of half sand/perlite, half peat. Cut the ends of the cutting in a wedge
shape, but be careful not to crush them. Use rooting hormone on the ends if you wish. Make a hole in the soil with
a stick, then insert the cuttings up to a third of the way into the potting medium. Keep moist, but not soggy, and
mist regularly. Keep in partial shade. Old foliage will turn yellow and fall off. When new shoots begin to grow,
you can be sure the cutting has rooted. Juniper cuttings can take a long time to root, so be patient.
Seeds: Do not always breed true to seed, not having the same characteristics of the parent plant. To start seeds
indoors. Remove pulp, pour boiling water over the seed, and let cool down over night. Press seeds into the surface
of moist, peaty soil. Keep cool, below 50F(10C) and fully exposed to light. Seed should germinate within 180 days if
consistently kept cool and moist.
Styles and Forms: Junipers can take well to any style except broom.
Species and Cultivars: J. chinensis "Shimpaku"- one of the most popular species for use in bonsai, characterised by a
red tone to the bark and clouds of hunter green scale foliage. Also known as Sargent's juniper. A natural defense
mechanism in times of stress, in it's natural habitat a shimpaku can limit its foliage mass by allowing entire branches
to die off. Natural deadwood is common on these in the wild where the bark and roots connecting the severed
branch also die off. Will produce dark blue berried with a white coating. Hardy to zone 5.
J. chinensis "San Jose" - San Jose Juniper. Have both scale and needle foliage. Grayish, flaking bark. Vigorous
growers. Hardy to zone 4.
J. chinensis "Torulosa" or "Kaizuka - "Hollywood Juniper" a variant of the Shimpaku. Tree like growth habit. Heat
tolerant. Hardy to zone 5.
J. communis - "Common or Ground Juniper" Extremely hardy. Slow growing with habits ranging from ground
cover, to shrub to small tree. Branches tend to be more brittle than other varieties. Hardy to zone 2.
J. procumbens "Nana" - "Dwarf Japanese Garden Juniper" sharper, scaly foliage that sometimes turns purplish in
winter. Tough species and relatively forgiving. A creeping habit, well suited for semi-cascade and cascading styles.
Do not usually produce berries or cones. Common in most nurseries and DIY stores, a reasonably priced shrub
with potential is easier to come by without spending a fortune. Hardy to zone 4.
J. rigida - Needle juniper. Slightly different, both in foliage and habit from other species of juniper. Also called
"Temple Juniper," this species has very sharp, needle like leaves, clustered in groups of three on slender shoots.
Because the shoots are slender, it can often give the tree an unkempt appearance, so regular pruning is required. At
the base of each needle is a dormant bud, which will usually produce a new shoot after trimming. The more severe
a trimming, the greater number of dormant buds will extend. This can lead to an overcrowded foliage mass
(inviting critters like spider mites). To prevent this from occurring, prune away the ends of older twigs once a
year- the newly growing shoots will grow on to replace the pruned twigs. In time, this process can be repeated as
the foliage mass grows to heavy again. Crowded branches, beside being appealing to pest, will lead to die back
within the inner parts of the tree as light and air cannot reach. Needle junipers also have stiffer, more brittle
branches than Chinese junipers, and more care must be taken when wiring. Needle junipers have a bad reputation
for dying without apparent cause. There is *always* a cause, but the plant's metabolism is so slow it can take
months before it starts to signs that it is in distress, and might already have been dead for some time at that point.
Hardy to zone 6.
J. squamata - Squamata junipers originated in Nepal. Slender, often floppy shoots are densely gathered with soft,
blue-green needles which point forward, almost hugging the shoot. These will extend as they grow, standing more
erect and exposing the dormant bud at the base. Naturally dense growth pattern. Young shoots are delicate, and
easily dislodged during pruning and wiring. They will regrow in time, but treat them with respect to avoid the
extra headache. Slow growing, resistant to Juniper Blight. Hardy to zone 4.
J. ashei - "Ashe Juniper" Native to Texas and parts of central America. Scale foliage. Hardy to zone 7.
J. californica - "California Juniper" Scale foliage. Native to the Mojave Desert, Arizona, Nevada, New Mexico.
Though native to high altitudes, can be grown at low altitudes without difficulty. Hardy to zone 8.
J. virginiana - "Eastern Red Cedar" Not a true cedar. In nature can grow to be 40-50 ft tall. Reddish brown shaggy
bark with deep green scale foliage. Well suited for upright, literati and forest styles. Hardy to zone 2.
J. prostrata - Low ground, spreading habit. Grey-green foliage and flaky bark. Twisted and gnarly in natural form,
well suited for deadwood styles. Hardy to zone 3.
Other Information: Avoid cultivars with the "blue" title in the name (ex. "Blue Star"). These tend to be weaker,
more prone to disease and infestations.
In nature, junipers sometimes allow branches to die off to keep the balance of the tree (demands of the foliage
versus the ability to provide water from the roots) in tact. This can also happen in pot-grown bonsai, and if a
branch dies off for no apparent reason, it may simply be the tree following it's natural inclinations to balance out
it's growth.
Juniper (Juniperus)
Shimpaku Juniper, featuring extensive Jin and Shari
work. Photo courtesy of Golden Bonsai Nursery
work. Photo courtesy of Golden Bonsai Nursery
Shimpaku Juniper from Golden
Bonsai Nursery
Bonsai Nursery
J. procumbens "Nana" from
Golden Bonsai Nursery
Golden Bonsai Nursery
Juniper, "Blue Star"- ill suited for
bonsai cultivation, and
unhealthy to boot.
bonsai cultivation, and
unhealthy to boot.