Woody > Thuja > Thuja occidentalis > Thuja occidentalis 'Jantar'
Thuja occidentalis
'Jantar'
Jantar Arborvitae
Origin: A mutation of Thuja occidentalis ‘Smaragd’, it was discovered in 2000 by Jacub Jablonski, in Lysomoice, Poland.
Mike's
Opinion
"
An unusual cultivar of the Thuja genus, this cedar has striking foliage that is an amber-yellow colour in the winter season that breaks up the repetitiveness that occurs with a mass planting of green cedars. Moreover, the colour provides excellent summer and winter interest. The narrow, pyramidal form and slow-growing nature allows the shrub to grow in various locations where others may not fit. Thuja occidentalis ‘Jantar’ is relatively low maintenance, readily grows in almost any soil type and fills many roles making this cultivar a good choice for the practical homeowner. Overall, it is an exceptional alternative to traditional Thuja occidentalis cultivars for use in a landscape setting. - Tamsyn Richards
Michael Pascoe, NDP., ODH., CLT., MSc. (Plant Conservation)
"
| Family |
| Cupressaceae |
| Genus |
| Thuja |
| Species |
| occidentalis |
| Cultivar |
| 'Jantar' |
| Category |
| Woody |
| Type |
| Shrub (evergreen) |
| USDA Hardiness Zone |
| 4 |
| Canadian Hardiness Zone |
| 3a |
| RHS Hardiness Zone |
| H7 |
| Temperature (°C) |
| -32 - -29 |
| Temperature (°F) |
| -25 - -20 |
| Height |
| 1 m |
| Spread |
| 0.5 m |
Photographs
Description and Growing Information
Flowering Period
| General Description |
| Jantar Arborvitae is a sterile coniferous perennial cultivar shrub with vivid yellow to amber-yellow foliage, depending on the season. The foliage is compact and dense in comparison to other Thuja varieties (Jablonski, 2011). This shrub is medium and has an upright, narrow, pyramidal shape with a sharp point at the top. The branches are not visible due to the dense growth habit, but the bark ranges from yellow green to grey-brown (Jablonski, 2011). |
| Landscape |
| An excellent shrub for its stunning yellow foliage, it has many uses in the landscape. It can be used as hedges and screens because of its dense foliage and narrow form, be an accent plant, used in mass planting, and for general garden use (Amber Gold Arborvitae, 2020). The shrub can be planted in large pots, and suggested use include Modern and Courtyard style landscapes (Thuja Occidentalis Jantar, n.d.). |
| Cultivation |
| Grows best in an average to moist soil that is consistently hydrated but does not have a preference to the type of soil. It prefers full sun to partial shade for the foliage to achieve its stunning colour. This cultivar is tolerant of pollution in urban settings but will grow best in a protected location. Moderate trimming in the spring season will encourage new growth in the summer but one should prune Jantar Arborvitae to remove deadwood and disease (Thuja Occidentalis Jantar, n.d.). |
| Shape |
| It is a medium-sized shrub that has dense foliage with leaves held tightly to the twigs; the trunk and branches are not visible. It is upright, pyramidal with narrow spread shrubs, with lateral, robust branches and forms a sharp point at the apex (Jablonski, 2011). |
| ID Characteristic |
| With a significantly denser, yellow with an orange tinge foliage, this cultivar sticks out compared to others. The leaves are rounded, possess a scale-like texture and an ovate shape. This is a sterile cultivar and will not produce cones or seeds. |
| Pests |
| Jantar Arborvitae is susceptible to the same biotic disorders and pests as its parent species and as other cultivars; it has no notable resistances or additional vulnerabilities. Thuja occidentalis is vulnerable to bagworm, leaf miner, scale insect, red spider mites, heart rot, canker, and blight (Beck & Renwald, 2001). Additionally, the foliage can suffer from desiccation in extremely arid conditions, however Jantar Arborvitae has proven to be winter-hearty and sun-tolerant (Jablonski, 2011). |
| Habitat |
| Horticultural origin. |
| Bark/Stem Description |
| Mature bark ranges from grey-brown to grey-red, with the younger branches possessing a yellow-green colour. Both the mature and young bark/branches have a smooth, dull texture. The shrub is multi-stemmed and has strong apical dominance; the lateral branches and stems form a pyramidal shape (Jablonski, 2011). |
| Flower/Leaf Bud Description |
| Lateral buds have an opposite arrangement on the stem, with a terminal bud that is dark green and matures to yellow leaves. Buds have a conical shape with striate scales and are 0.3 cm long on average (Valentine, 2006). Buds have a smooth, glossy texture similar to fully developed leaves. |
| Leaf Description |
| Rounded scale-like leaves, that are situated in an opposite arrangement on the stem and are sessile. They have an ovate shape, with an apiculate apex, cuneate base, and the margin is entire. Mature leaves are green to yellow-green in colour and are estimated to be 0.3 cm long, and 0.1 cm wide (Jablonski, 2011). The leaves are smooth, lustrous, and have no visible venation. Young foliage ranges from grey-orange to yellow-green in colour. |
| Flower Description |
| Jantar Arborvitae is a sterile cultivar and does not produce flowers (Jablonski, 2011). |
| Fruit Description |
| Jantar Arborvitae is a sterile cultivar and does not produce fruit (Jablonski, 2011). |
| Colour Description |
| The word ‘Jantar’ is the polish term for amber; Jantar Arborvitae or Amber Gold Arborvitae has a unique amber-gold colouring. (Amber Gold Arborvitae, 2020). This colouring is a natural mutation from the Thuja occidentalis ‘Smaragd’ and varies from other cultivars with similar appearance because it has an orange tinge. Jantar Arborvitae foliage emerges yellow in the early spring; this foliage changes to amber-gold during the winter (Thuja Occidentalis Jantar, n.d.). |
| Texture Description |
| A medium textured plant with scale-like leaves, the leaves are relatively soft to touch and glabrous. The shrub branches present a sharp texture in the landscape and maintain a similar appearance throughout the seasons. |
| Notable Specimens |
| There is a notable specimen in The Botanical Gardens of Fanshawe College in London, Ontario, Canada. |
| Propagation |
| Propagated by cuttings, it must be harvested during September to early October before dormancy (Conifer Propagation 101, n.d.). The cuttings must be between 15 to 20 cm long, and come from a disease-free, healthy shrub. Remove all foliage from the bottom 10 cm of the cutting (Richards, 2017). Dip these cuttings into plant rooting hormone and place in a mixture of semi-moist, 50/50 sand and peat moss media, cover the pot to retain humidity, and place in a cool location. The potting media must be monitored carefully and remain moist. The roots will develop over winter or in the following spring. Once the cutting establishes roots, fertilize the new shrub to promote further growth (Conifer Propagation 101, n.d.). |
| Ethnobotanical Uses (Disclaimer) |
| Thuja occidentalis has several medicinal and clinical applications. The first recorded use of Thuja occidentalis in a medicinal setting is during the 16th century when Indigenous people in Canada use the plant as a remedy for scurvy. Homeopaths also use this genus for treatment of psoriasis, rheumatism, cystitis, and even make “tinctures” from the plant to treat moles and tumours (Thuja Genus, n.d.). Research from Biwas et al. states that Thuja occidentalis shows anticancer potentials (2010). Scientists are researching the plant for clinical use in treating the common cold, and supportive therapy for antibiotic users (Naser et. al, 2005). Materials harvested from Thuja occidentalis can also be used to make fence posts, rails, chests, and guitar soundboards (Thuja genus, n.d.). |
References
Thuja genus (Arborvitae). (n.d.). American Conifer Society. https://conifersociety.org/conifers/thuja/
Thuja occidentalis 'Jantar' / Jantar arborvitae. (n.d.). American Conifer Society. https://conifersociety.org/conifers/thuja-occidentalis-jantar/
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