Cedrus atlantica (Glauca Group)
Blue Atlas Ceder
"
Cedrus atlantica (Glauca Group) is a beautiful ornamental tree that is a great addition to any garden with its silvery-blue/green colour, spiral needles and statuesque form. Blue Atlas Cedar should be planted where it can grow without crowding as it looks its best when the branches droop all the way to the ground, it requires a large amount of room for it's striking form to reveal itself.
"
Family |
Pinaceae |
Genus |
Cedrus atlantica (Glauca Group) |
Category |
Woody |
Type |
Tree (evergreen) |
Synonyms |
Cedrus atlantica 'Glauca', Cedrus atlantica var. glauca |
Pronunciation |
USDA Hardiness Zone |
6 - 8 |
Canadian Hardiness Zone |
6 |
RHS Hardiness Zone |
H4-H5 |
Temperature (°C) |
-23 |
Temperature (°F) |
-10 |
Height |
9 - 40 m |
Spread |
8 m |
General Description |
A large evergreen with intense blue to silvery-blue needles: a great specimen plant. Its open, upright pyramidal form has lower branches that spread out to about one third to half its height. The branches grow almost horizontally and can touch the ground. Growing rapidly when young, then slower as it ages, it can reach up to 40 m in height. It grows well in the heat and tolerates pollution and urban conditions. |
Landscape |
Ornamental or specimen plant. |
Cultivation |
Prefers full sun or partial shade with well-drained, moist, deep, loamy soil but can easily adapt to different soil types. Blue Atlas Cedar needs to be planted away from strong or direct winds since it is prone to wind burn. Tolerates pollution and urban conditions but is difficult to transplant. |
Shape |
Upright loosely and openly pyramidal. It has densely arranged branchlets with stiff, horizontal main branching; branching can be somewhat sparse, especially when it is young. |
Growth |
Slow |
ID Characteristic |
Blue Atlas cedar is classified as a true cedar. This tree has both male and female cones with the males growing on the lower half of the tree and the females forming on the top half. With short, silvery-blue needles that twist around the branchlets, branches that grow all the way to the ground, attractive barrel shaped cones and the fact that it easily adaptable to different soil conditions while being relatively pest free makes it a valuable addition to the garden. |
Pests |
Usually pest and disease free but can suffer from tip blight, root rot (if the soil is not well drained), black scale and the Deodar weevil; however, pest control is not usually necessary as most infestations are minor. |
Habitat |
The Atlas Mountains of Northern Africa. |
Bark/Stem Description |
Grey and smooth for 20-30 years but eventually developing a plate-like pattern towards maturity. |
Flower/Leaf Bud Description |
Small and ovoid, with few scales. 2 - 5 cm long |
Leaf Description |
Slightly curved, simple, green to silvery-blue needles, 1.2 - 2.5 cm long, arranged spirally on long shoots and in rosettes on short spur growths. The needles are classified as evergreen, but persist for two-four years before being dropped and replaced. |
Flower Description |
Male flowers are erect catkins that can be up to 5 cm long. Females are erect, cone-like inflorescences, 1-1.5 cm long, surrounded by needles at the base. Male and female flowers occur on the same tree; males are borne on the lower half and females are typically on the top half. |
Fruit Description |
Monoecious. Male cones are solitary, erect and finger shaped. They are 5 cm – 7.5 cm long and 1 cm - 1.5 cm wide and are found on the lower part of the tree. They shed their pollen in autumn. Female cones take two years for the seeds to ripen. They start off purple-green when pollinated, turn mauve and then finally light brown. The cones range from 8 -15 cm in length, are upright, barrel-shaped and resinous. They have very closely appressed broad scales that have two seeds attached to each scale. The seed is an irregular triangular shape with seed resin vesicles on each side and a membranous, broad wing that is larger than the seed. |
Colour Description |
The needles are green to silvery-blue. The female cones are a purple green colour when first pollinated and change to mauve and then finally, light brown when they are mature. The bark is light to medium grey. |
Texture Description |
The foliage is finely textured however overall the plant has a rather coarse texture. |
Notable Specimens |
Royal Botanic Gardens, Kew, London, England. Westonbirt, The National Arboretum, Tetbury, Gloucestershire, England. |
Propagation |
Place seeds into a sealable plastic that has been filled halfway with dampened, milled, sphagnum moss and then cover the seeds with more moss. Seal the bag and put it in the refrigerator or somewhere that remains between 0-1°C for about three weeks. Check the moss and keep it moist but not wet. Conversely, direct sow in pots or flats and stratify as above. Germination should occur within 3-5 weeks. If using the bag method check seeds every few days after the three week period for signs of germination. As soon as the seed coat splits pot the seeds and grow on in a protected nursery location. |
Ethnobotanical Uses (Disclaimer) |
The wood is durable and decay resistant. |