The Juniper Berry ( Juniperus communis var. communis ) is a shrub or small coniferous tree that is known for its berries; that are an essential ingredient in Gin. The name ‘Juniper’ is actually an old French word for ‘Gin’. Juniper berries are also used to flavour beer and meat. The Juniperus communis plant is also used medicinally and is a popular essential oil.
Juniperus communis is native to the cooler temperate climates of Britain; mountainous North Africa and the Himalayas but will cope with a wide range of zones; including sub-tropical regions. In fact it has the largest geographical range of all woody plants. This species is can be grown as a bonsai.
Suitable for Cold to Sub-Tropical Climates; as well as dry Mediterranean regions.
Growth
Juniperus communis var. communis is an upright evergreen shrub, that can grow to a height of 8-10 metres and 3-4 metres wide. Its leaves or spikes are a green to blue-green colour, with a whitish coloured stripe through the centre and average in size from 10-20 mm in length.
This species is dioecious, meaning that each plant is either a male or a female; the two sexes are not found on the same plant. In order to produce fruit and seeds; both sexes are needed and for best results should be planted close by; at around a 4-5 metre spacing.
The male cones are oblong and small at approximately 3 mm long, a creamy colour and look bumpy like a small creamy coloured mulberry. The female cone is more of an oval shape and starts off a pale green colour. They are approximately 4-6 mm and are smoother but somewhat scaly. It takes at least 18 months from pollination for the female cones to ripen to the berry looking dark blue – almost black colour. Berries (cones) at maturity only grow as large as 10 mm. Inside the female cone is sectioned, usually having 3 sections but are possible. Each section of the female cone holds a single seed.
A note about seed germination of Juniperus communis
This species is very hardy and will grow in most soil types and climate zones, however seed germination is not for the faint hearted. It is a more difficult seed to germinate and requires several months of treatment prior to attempting germination. This includes cold stratification, followed by a period of room-warm temperatures and yet another dose of cold stratification. This is necessary to break the seed dormancy and can take up to 9 months. In the wild the seeds are eaten and dispersed by birds; the acid in the digestive tract of birds can help bring the seeds out of dormancy.
FAMILY:
Cupressaceae
CLIMATE:
Cold to Sub-Tropical and dry climates.
TEMPERATURE RANGE:
-30°C to 40°C / -22 to 104°F
SOIL TYPE:
Well draining soil preferred but will grow in most soils from sand to clay!
LOCATION:
Full Sun – Part Shade.
HEIGHT:
Up to 10 metres (32 feet)
WIDTH:
Up to 4 metres (14 feet)
pH:
6.0-8.0
GROWTH TYPE:
Evergreen, slow growing.
WATER REQUIREMENTS:
Low
POLLINATION:
Requires both Male and Female plants to pollinate, wind pollinated.
MATURITY:
5-7 years
GERMINATION RATES:
45-70%
GERMINATION TIME:
12 weeks stratification – see the Germination Instructions tab.
SEEDS PER GRAM:
Approximately 80
MEDICINAL QUALITIES:
Yes.
WEED POTENTIAL:
No.
EDIBLE:
Yes.
SEED STORAGE & VIABILITY:
Cold Storage at 4°C (Fridge) up to 5 years.
FACTS ABOUT JUNIPERUS COMMUNIS (Juniper Berry)
Juniper berries are believed to have many health and medicinal qualities; both as an edible fruit and an essential oil.
The leaves, stems and roots are used to make a tea and are said to have a spicy gin flavour.
Please note: Native Americans used the berries as a contraceptive in females; it is believed to cause uterine contractions which can cause abortion; so please do not eat these berries if you are pregnant.
Germination Instructions
HOW TO GROW JUNIPERUS COMMUNIS (Juniper Berry)
Two methods are noted here, we have found the best rates with the first method (citric acid + long cold stratification).
METHOD 1
Step 1
In nature these seeds germinate best after being passed through a birds intestines, as this will help break the seeds dormancy. As this is not generally possible in practice; this can be mimicked by soaking them in a 1% citric acid solution for 4 days. CITRIC ACID CAN BE PURCHASED AT MOST SUPERMARKETS.
Step 2
Place the seeds into a plastic zip-lock with a 50/50 mix of moist (NOT WET) sand and soil, enough to keep seeds separated. Seal the bag firmly.
Write the date and place bag into the crisper of a fridge for 30 weeks. Check weekly to be sure the medium is not drying out and remoisten with a mist spray bottle if necessary. The treatment will not be successful if the seeds are allowed to dry out! Also keep an eye out in case any seeds have begun to sprout. This is not very common, but can happen – if so remove carefully and plant into trays/small pots.
Step 3
Once the cold stratification period is over sow each seed about 3mm deep into seed trays of a good quality seed raising mix. Add propagating sand if necessary to ensure good drainage. Moisten and then move into part sun (not full sun) position. Dappled shade or a well lit area out of any direct sun is also suitable.
Keep soil moist at all times, but not wet and boggy. If the soil dries out for too long at any stage, the seed may become dormant again … and the whole process may need to be restarted.
Earliest seeds will germinate after 3-6 weeks but many may take much longer, patience is needed.
Ideal temperatures for germination are 15-20°C/59-68°F
METHOD 2
Step 1
Alternatively you can place them in boiled water for 10 seconds and leave to soak for 24 hours in room temperature water. Please note that germination rates may not be as high with this method.
Step 2
After soaking place the seeds into a plastic zip-lock with a 50/50 mix of moist (NOT WET) sand and soil, enough to keep seeds separated. Seal the bag firmly.
Write the date and place bag into the crisper of a fridge for 12 weeks. Check weekly to be sure the medium is not drying out and remoisten with a mist spray bottle if necessary. The treatment will not be successful if the seeds are allowed to dry out! Also keep an eye out in case any seeds have begun to sprout. This is not very common, but can happen – if so remove carefully and plant into trays/small pots.
Step 3
Once this step is complete, move the zip lock bag into an area with fairly stable daytime temperatures around 15-20°C/59-68°F. Leave the seeds in this area for another 12 weeks. Again check regularly for moisture and possible germination.
Step 4
After warm stratification, it is back to the fridge for 12 weeks as step 2. Again check weekly to make sure they do not dry out and re-moisten if needed.
Step 5
After this last 12 weeks in the fridge they are ready to be sown. Sow each seed about 3mm deep into seed trays of a good quality seed raising mix. Add propagating sand if necessary to ensure good drainage. Moisten and then move into part sun (not full sun) position. Dappled shade or a well lit area out of any direct sun is also suitable.
Earliest seeds will germinate after 3-4 weeks but many may take much longer, patience is necessary.
Ideal temperatures for germination are 15-20°C/59-68°F
NOTE: if you were to just plant them in the garden, they would take on average 2-5 years to germinate – and only if your location had the correct winter conditions necessary!
Once germination has begun:
Once sprouted, keep the seedlings in the same conditions/climate that they are clearly happy with – only moving if they look like they are getting leggy and searching for sunlight.
They can be transplanted carefully once they are strong enough to handle and are best kept in pots until they are at least 2-3 years old.
If the seedlings have been kept in a more shaded position, they will require hardening off to full sun prior to planting out.
Transplant to final position after any threat of frost has passed in Spring at approximately 3 years of age. A full sun position is preferred.
Once established, they will survive severe cold, quite extreme heat and will only require light watering. Additional water advised when fruiting.
Junipers can take between 5-7 years to fully mature. It is only at flowering age that you will be able to tell the sex of your plants.
