Native to the cool temperature climates of the northern hemisphere, common junipers (Juniperus communis) have a nearly complete circumpolar distribution—occurring naturally throughout parts of North America, Europe, and Asia. This makes the common juniper one of the most widely distributed shrubs in the world. In cultivation, J. communis has not received quite as much attention as Chinese juniper (J. chinensis), but there are still dozens of common juniper cultivars to choose from. These hardy evergreen conifers, members of the Cupressaceae family, are variable in form depending on the cultivar and conditions where they are growing. The species form is typically a low-spreading shrub no more than about 5 feet tall and up to 13 feet across, but there are cultivars with tall, tree-like form, as well as creeping groundcover forms that grow just a few inches in height. Varieties bred for landscape use are rarely more than 15 feet tall, and many are much smaller. All common junipers are characterized by short needle-like, aromatic leaves and berry-like green cones that turn a deep purple/blue as they ripen.
Common juniper, like most conifers, is usually planted during mild weather of spring or early fall. The rate of growth varies somewhat by variety, but most are slow-growing shrubs, rarely adding more than about 6 inches per year.
Growing beautiful juniper trees from tiny seeds is an incredibly rewarding experience for any gardener With their attractive evergreen foliage and natural hardiness, junipers make excellent landscape specimens. By propagating junipers yourself, you can produce an endless supply of free plants with unique new genetics
In this comprehensive guide, I’ll walk you through each step of successfully growing junipers from seed. With the right harvesting, stratification, and care, those tiny juniper seeds can flourish into amazing landscape conifers. Let’s get started!
Gathering and Preparing Juniper Seeds
The first step is collecting ripe, mature cones from existing juniper trees in late summer or early fall. Look for cones that have turned from green to a blue, gray, or brown color. This indicates the seeds inside are ready for harvest.
Small sharp pruners or pole saws allow you to snip off clusters of cones from high branches. Place cones immediately into paper bags to prevent seed loss. Then spread them out to continue drying for 1-2 weeks.
When cones have fully dried, it’s time to extract the tiny seeds hidden inside each fleshy scale I put cones into an old blender with some warm water Pulse it briefly, just 1-2 seconds, to crack open the scales without damaging the seeds.
Pour the mixture into a large bucket of water. Seeds will sink while cone debris floats. Skim off debris and pour the seeds into a fine mesh strainer to drain. Spread seeds on paper towels and allow to thoroughly air dry before storage.
The Importance of Stratifying Juniper Seeds
Juniper seeds have a naturally tough outer coating evolved to resist germination. They require a process called stratification to break dormancy. Stratification mimics seasonal cycles of winter cold and summer warmth in nature.
Before stratifying, soak dry seeds in room temperature water for 48 hours. This rehydrates them in preparation for the months ahead. Now they’re ready for the first “warm” phase.
Place seeds into breathable containers like cloth bags or plastic tubs. Mix with a slightly moist growing medium like sand, soil, or peat-free compost. Put the containers outdoors for 3 months, allowing seeds to experience autumn’s cooler temperatures.
For the “cold” phase, bring the seeded containers indoors and store in your refrigerator for 3 more months. Check moisture levels periodically and sprinkle in water if needed. Tiny white roots may emerge from some seeds by early spring.
Planting Pre-Sprouted Juniper Seeds
Once those first tiny roots appear, quickly plant sprouted seeds into individual containers filled with porous bonsai soil mix. Gently scoop out each one, being careful not to disturb the emerging root.
Place sprouted seeds just below the bonsai mix surface and lightly water each container. Cover seeded pots with plastic to retain moisture during establishment. Provide bright, indirect light but avoid hot direct sunlight.
Watch for the first true needles to develop on seedlings before removing the plastic domes. Keep soil moist but not saturated at all times. Consistent moisture is crucial as delicate new roots rapidly grow and fill pots.
Caring for Young Juniper Seedlings
The first year is critical for establishing hardy, healthy juniper seedlings. Place pots outdoors after your last spring frost once temperatures warm. Provide partial shade cloth to protect from harsh sun as seedlings adjust.
Monitor soil moisture closely and water whenever the top inch becomes dry. I like to use a spray bottle to gently mist seedling foliage, boosting humidity around the emerging needles. This prevents desiccation damage.
Apply a balanced liquid bonsai fertilizer monthly to support rapid growth. Repot seedlings into progressively larger containers each spring until root systems fill one gallon pots. Now they are ready for transplanting!
Troubleshooting Tricky Juniper Seeds
You may not achieve 100% germination success, even with ideal harvesting and stratification. Genetic variability, weather, age, diseases, and storage conditions all affect viability. Here are some troubleshooting tips:
-
Soak seeds in a mild bleach solution to kill fungus before stratifying. Rinse thoroughly.
-
Try extending the warm stratification period to 4-6 months if cold stratification alone fails.
-
Use fresh, newly harvested seeds whenever possible for best germination rates.
-
Protect seeded containers from rodents who love munching on juniper seeds! Use hardware cloth.
-
Ensure even moisture levels. Irregular watering causes seeds to shrivel and die.
With persistence and careful attention to their needs, you can coax even reluctant juniper seeds into flourishing seedlings. Just remember that nature has its own timeline.
Which Juniper Varieties are Best for Beginners?
While all junipers can be grown from seed, some easier species for beginners are:
- Common Juniper (Juniperus communis)
- Chinese Juniper (Juniperus chinensis)
- California Juniper (Juniperus californica)
- One-Seed Juniper (Juniperus monosperma)
- Eastern Redcedar (Juniperus virginiana)
I recommend starting with vigorous varieties suited for your growing zone rather than slow, tricky ones like savin juniper. Ask local nurseries which types thrive in your climate.
Choose plants with excellent disease resistance to avoid headaches with fungal issues. And look for trees with attractive year-round foliage color like the steel blue needles of blue point juniper.
Why Grow Your Own Juniper Trees from Seed?
You may be wondering why you shouldn’t just purchase juniper trees instead of propagating your own from seed. Here are some great benefits of growing your own:
-
Unique genetics: Seed-grown trees have brand new, diverse DNA.
-
Free trees: Growing your own junipers costs nothing beyond supplies.
-
Early training: You can shape and train growth from a young age.
-
Reduced transplant shock: Seedlings handle transplantation better than nursery trees.
-
Fun experience: It’s incredibly rewarding to grow a tree from seed to sapling!
As long as you provide the proper care, you’ll be rewarded with gorgeous, thriving junipers perfectly adapted to your site.
Final Tips for Juniper Seed Success
In closing, follow these key tips when growing juniper trees from seed:
-
Start seeds in early fall to allow 3 months warm plus 3 months cold stratification.
-
Use fresh, ripe cones gathered right after they mature on trees.
-
Ensure constant even moisture during the lengthy stratification period.
-
Transplant sprouted seeds into individual pots as soon as you see the first roots.
-
Let young seedlings establish 1-2 years before putting them in the ground.
-
Choose resistant species and cultivars suitable for your growing zone.
With the right planning and care, those tiny juniper seeds can transform into magnificent landscape conifers under your green thumb!
Types of Common Juniper
As a landscape plant, the common juniper is sometimes considered inferior to Chinese juniper, of appeal mostly to native plant enthusiasts. This reputation has slowly changed, thanks to the extremely tolerant nature of this plant. While its available cultivars are still less plentiful than those of Chinese juniper, there are several excellent varieties of common juniper to consider:
- Juniperis communis Gold Cone is a 3- to 5-foot-tall shrub with a columnar form and light greenish leaves.
- Juniperis communis Repanda is a prostrate groundcover form, growing 1 to 2 feet tall and 8 to 9 feet wide.
- Juniperis communis Compressa is an upright, cone-shaped shrub growing just 2 to 3 feet tall.
- Juniperis communis Hibernica is a lovely pillar-shaped shrub growing to 15 feet tall.
- Juniperis communis Blue Stripe is a 2-foot tall, 6-feet-wide prostate form with leaves that have a distinctive blue stripe.
There is also an important variation, Juniperis communis var. depressa, which has several named cultivars, including Blueberry Delight and Copper Delight. The depressa variation occurs naturally in the Eastern U.S., growing about 3 to 4 feet tall and up to 12 feet wide. It is used mostly as a ground-cover plant for large areas.
Light
Common juniper is a sun-loving evergreen that should receive full sun for the majority of the day. If a common juniper does not receive enough light you may notice stalled or stunted growth. Common junipers cannot survive in full shade conditions.
How To Grow Juniper Tree From Seed | Growing juniper Berries
FAQ
How long does it take for juniper seeds to germinate?
Germination is the first crucial step in a juniper tree’s life cycle. For optimal results, seeds thrive in temperatures between 65°F to 75°F (18°C to 24°C). Moisture is key; seeds need consistent moisture but should never be waterlogged. Depending on the species, germination can take anywhere from 2 to 6 weeks.
Are junipers easy to grow?
The Blue Point is drought tolerant, easy to grow, and perfect for privacy!
Do juniper seeds need cold stratification?
Rather than the acid treatment, two to three months of warm stratification could be used. As an alternative for cold stratification, the seed may be sown in the fall. Germination is delayed at temperatures above 15°C (60° F). Germination is often delayed in juniper seeds, as seeds are consistently highly dormant.
How to start a juniper from a cutting?
Cut off the stem bark with a sharp knife and remove the tip of the shoot and the lower needles. Then plant the cutting into a mixture of all purpose soil and sand and place the whole thing in a bright place with high humidity at around 20°C. Keep the soil moist at all times.
How do you propagate juniper by seed?
Seed propagation is a popular method for creating new Juniper varieties. The process begins by collecting ripe seeds in the fall, which are then dried and stored in a dry paper container, such as a box or bag, in a cool, dark place like a garage, avoiding heated areas.
Can junipers grow from seeds?
Though it can be a slow process taking up to three years, common junipers are not difficult to grow from seeds. Common junipers are dioecious, meaning that individual trees are either male or female, and must be planted nearby the opposite sex in order to cross-pollinate and produce fruit.
How do junipers grow?
It stems from the male pollen from one species combining with the female tree that holds the seeds. When you develop a cutting into a bonsai, it simply has the same strand as the tree you took it from. Many countries enjoy the diversity that this brings, mixing the genes of various Junipers.
When should you collect juniper seeds?
Seed propagation is a popular method among gardeners and breeders for creating new Juniper varieties. The process begins by collecting ripe seeds in the fall, which are then dried and stored in a dry paper container, such as a box or bag, in a cool, dark place like a garage, avoiding heated areas.
How do you grow a juniper tree?
Juniper needs quite a lengthy pretreatment to help it to germinate. Seed should be soaked for two days (if it’s been stored dry) and mixed with a mixture of equal parts horticultural sand or a sand/compost mixture. Use 50% leafmould or peat-free compost and 50% horticultural sand.
How do you harvest American juniper seeds?
Timing is key when collecting American Juniper seeds. Aim for a mast year, when junipers produce a heavy crop of berries. This occurs every two to five years, so patience is a virtue here. Once the berries are ripe, typically in the fall, gather them up. It’s a straightforward process: pick, pluck, and prepare for the next step.