Common Name: Creeping Juniper

General Information

Juniperus horizontalis is a prostrate to decumbent, evergreen shrub with a depressed crown, creeping branches and erect branchlets[]. The plant often forms wide, low mats of growth, and is seldom more than 60cm tall[].
The plant is harvested from the wild for local use as a food, medicine and source of materials. It is used in soil stabilization projects and is also grown as an ornamental, where it makes an excellent ground cover.
Juniperus horizontalis is extremely widespread and common in many areas and is not threatened in any way. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

None known

Botanical References

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Range

Northern N. America - Alaska to Nunavut and Labrador, south to British Colombia, Colorado, Illinois and New York

Habitat

Usually on more or less open ground; on sandy beaches, sand dunes, dry rocky slopes and outcrops, limestone ridges, dry 'barrens', grassland, open bogs, heathland and stream banks, often forming wide patches; at elevations up to 1,160 metres[]

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Shrub
Height	0.60 m
Growth Rate	Slow
Pollinators	Wind
Self-fertile	No
Cultivation Status	Wild

Cultivation Details

Juniperus horizontalis is a very cold-hardy plant, able to tolerate temperatures down to around -30°c when fully dormant[]. It occurs in areas with continental climates that are typically dry and often experience great annual and diurnal temperature variations[].
Succeeds in a sunny position in most soils so long as they are well drained, preferring a neutral or slightly alkaline soil[] and succeeding on chalk[]. It is often found in the wild on sandy, poorly developed soils, and has a preference for high calcium soils[]. Succeeds in dry soils[]. The plant tolerates a pH in the range 4.4 - 8.5[].
Creeping Juniper is a desirable species for horticulture in cool temperate to cold regions, and has been cultivated since the early 19th century. There are now numerous garden forms (cultivars) known, selected both in Europe and North America and widely used in gardens and parks[].
Juniperus horizontalis currently holds the record as the smallest conifer in the world, since cone-bearing individuals only 4cm tall have been recorded[].
An aggregate species[]. There are many named varieties selected for their ornamental value[]. 'Bar Harbour' is very salt-resistant[].
Juniperus horizontalis, a prostrate species, hybridizes with the trees Juniperus virginiana and Juniperus scopulorum, and is closely related to both[].
A dioecious species, both male and female forms must be grown if seed is required.

Edible Uses

The fruits are roasted and used in the preparation of a coffee-like beverage[]. The seed cones mostly mature in 2 years - they are of two distinct sizes, generally with curved peduncles, globose to ovoid, 5 - 7mm in diameter, blue-black to brownish blue when mature, lightly glaucous, soft and resinous, with 1 - 3 seeds[].

A tea is made from the young branch tips[, ].

Medicinal

An infusion of the branches, or fleshy cones, has been used in the treatment of coughs, colds and fevers[]. The cones or branches can also be used as a steam bath[].

An infusion of the seeds has been used in the treatment of kidney problems[].

Agroforestry Uses:

A good ground cover plant for a sunny position[], eventually making a dense cover though it requires weeding for the first year or so[]. An excellent ground cover on sandy soils and in rockeries[].
With its prostrate growth and creeping branches that hug the ground, this species is an effective soil stabilizer on sandy slopes[].

Other Uses

The bark has been crushed and used as a soft hygienic pad in cradles[]. It has also been used to make mats[].

The young twigs and leaves have been burnt as an incense[].

Propagation

The seed requires a period of cold stratification. The seed has a hard seedcoat and can be very slow to germinate, requiring a cold period followed by a warm period and then another cold spell, each of 2 - 3 months duration[, ]. Soaking the seed for 3 - 6 seconds in boiling water may speed up the germination process[]. The seed is best sown as soon as it is ripe in a cold frame. Some might germinate in the following spring, though most will take another year. Another possibility is to harvest the seed 'green' (when the embryo has fully formed but before the seedcoat has hardened). The seedlings can be potted up into individual pots when they are large enough to handle. Grow on in pots until large enough, then plant out in early summer. When stored dry, the seed can remain viable for several years[].
Cuttings of mature wood, 5 - 10cm with a heel, September/early autumn in a cold frame. The cuttings root easily[]. Plant out in the following autumn[, ].
Layering in September/early autumn. Takes 12 months[].