A genus of 125 species of trees and shrub that are part of the larger family called Rhamnaceae that includes many more plants. Rhamnus are widespread in the Northern Hemisphere and are also native to South Africa, eastern Africa and Brazil.
Most prefer full sun to partial shade on any reasonably fertile soil.
Buckthorns to not like root disturbance and should be transplanted while very small.
Propagation is from sowing ripened seed in autumn, or layering.
Deciduous species can also be reproduced from softwood cuttings taken during early summer. Evergreen species can be reproduced from half hardened cuttings taken during summer.
Rhamnus alaternus ( Italian Buckthorn )
A fast growing, thornless, upright, open, evergreen shrub to small tree, native to the Mediterranean and Black Sea regions. Some records include: 2 years - 8 feet; 20 years - 20 x 17 feet; largest on record - 47 x 27 feet with a trunk diameter of 1.3 feet.
Tolerant of shearing, it makes an excellent tall hedge or screen.
The finely-toothed leaves, are up to 4 x 2 inches in size.
The leathery foliage is glossy deep green.
The small yellowish-green flowers borne in axilliary clusters, during late spring
They are followed by berries during late summer, that are green, ripening to red then black.
The stems are reddish-brown.
Hardy zones 7 to 10 in sun or partial shade on very well drained soil. Italian Buckthorn likes calcium in the soil and hates soils that are poorly drained where root rot may occur. The Italian Buckthorn thrives especially well on the west coast in the U.S. This very tough plant is very tolerant of drought, salt air and pollution.
John Edwards
Very fast growing, longer lived and dieback resistant. The foliage is glossy bright green.
Variegata
Also called Argenteo-Variegata. The very attractive, oval leathery foliage has a gray-green center with a wide white margin.
It is fast growing and bushy.
Rhamnus alnifolia
Native to North America, it reaches up to 4 feet with ovate to elliptical leaves, up to 4 inches in length.
Hardy north to zone 2
Rhamnus alpinus
A deciduous shrub, reaching a maximum height of 13 feet, that is native from Spain to Greece.
The finely toothed leaves, are up to 4 x 2 inches.
The tiny bright green flowers, borne during late spring, are followed by red drupes.
The stems do NOT have thorns.
Hardy zones 6 to 9
Rhamnus betulifolia ( Birchleaf Buckthorn )
A deciduous large shrub to small tree, native to moist canyons in the western U.S from southern Nevada to southwest Colorado, Arizona, New Mexico and western Texas; south into central Mexico. It is very similar to Rhamnus caroliniana.
Some records include: 10 years - ; largest on record - 25 x 45 feet with a trunk diameter of 1 foot.
The elliptic leaves, are up to 6 x 1.6 inches in size.
The foliage is
The flowers borne in clusters, during
They are followed by
Hardy zones
Rhamnus californica ( Coffeeberry )
An attractive moderate growing, upright evergreen shrub native to southern Oregon, California, southern Nevada, central & southern Arizona and New Mexico.
Some records include: 10 years - ; largest on record - 30 x 40 feet with a trunk diameter of 1 foot.
The finely toothed, elliptical to oval leaves, are up to 5 x 2 inches in size.
The foliage is reddish at first, turning to glossy green.
The bright greenish-yellow unisex flowers borne late spring into early summer.
They are followed by round berries that are red ripening to black.
Hardy zones 7 to 10 tolerating as low as 0 F
Ed Holm
Attractive shrub reaching maximum size of 6 x 15 feet. Glossy mid green foliage.
Eve Case
Attractive shrub reaching maximum size of 5.5 x 7 feet bearing tasty fruit.
Hardy to as low as -7 F
Mound San Bruno
Attractive shrub reaching maximum size of 6 x 15 feet.
Rhamnus caroliniana ( Carolina Buckthorn )
A strong branched, medium size tardily deciduous tree native to eastern North America from central Missouri to northeast Indiana to southwest Virginia; south to central Texas to central Florida. It is not common in the cultivation or in the wild where it is found in moist deciduous forests and river bottomlands.
Some records include: fastest recorded growth rate - 3 feet; largest on record - 50 x 20 feet with a trunk diameter of 1.3 feet.
The almost smooth edged, taper pointed, elliptical leaves, are up to 7 x 2 inches in size.
The strongly veined, handsome foliage is glossy deep green, turning striking golden-yellow and orange during autumn.
The greenish-white flowers borne in clusters, during mid spring.
They are followed by persistant, attractive, glossy red, later turning to black fruits, up to 0.4 inches. The flesh is dryer than that of Rhamnus purschiana. This is among the very few Rhamnus species with edible berries.
The slender gray twigs have pale lenticels and yellow-brown buds.
The smooth bark is ashy gray. Very old trees may have slightly furrowed bark.
Hardy zones 5 to 9 in sun or shade and is heat tolerant. It transplants poorly and is best grown from seed.
Rhamnus cathartica ( Common Buckthorn )
A thorny deciduous large shrub to small tree native to temperate regions of Eurasia as well as northern Africa. Some records include: fastest recorded growth rate - 4 feet; 10 years - ; largest on record - 61 x 65 feet with a trunk diameter of 2.5 feet. It may form dense thickets and in parts of North America is considered invasive.
The finely toothed oval to rounded leaves, are up to 3 x 2.5 inches in size.
The foliage is glossy mid green above, furry light green beneath; turning yellow in late autumn to early winter. The leaves appear very early in spring.
The small unisex flowers borne in axilliary clusters, during late spring.
They are followed in autumn with fleshy berries, up to 0.5 inches, that are red, ripening to black and persisting into winter.
The bark on young stems is dark with white lenticels, on older stems dark gray, rough, scaly and ridged. Some trees may have scaly orange-brown bark.
Hardy zones 2 to 7, it is tolerant of both flooding and drought as well as alkaline soil.
* photo taken on August 3 2010 @ University of Guelph Arboretum, Ontario
* photo taken on August 5 2010 in Clinton, Ontario
* photos taken on Aug 4 2013 in Bayfield, Ontario
* video found on Youtube
Rhamnus crocea ( Redberry )
A moderate growing, spreading evergreen large shrub to small tree that is native to all California, the Baja Peninsula, New Mexico and northwest Mexico.
Some records include: fastest recorded growth rate - 2 feet; largest on record - 30 x 45 feet with a trunk diameter of 1.5 feet.
The slightly tooth-edge, elliptic leaves, are up to 2.5 inches in length.
The foliage is glossy green.
The flowers are borne in small clusters.
They are followed by red fruit. This is among the very few species with edible berries.
The twigs are often thorny.
Hardy zones 7 to 10 tolerating as low as 0 F, requiring average rainfall between 22 & 50 inches.
Rhamnus dahurica ( Dahurian Buckthorn )
A fast growing, small deciduous tree native to temperate eastern Asia and Japan.
Some records include: largest on record - 35 feet
The leathery, gray-green leaves, are up to 6 x 2 inches in size.
The foliage is
The greenish-cream flowers borne during late spring.
They are followed by red berries.
The stout twigs are spiny.
Hardy zones 2 to 7
Rhamnus fallax ( Carniolian Buckthorn )
An evergreen shrub reaching a maximum height of 10 feet, that is native from southern Europe to the Middle East.
The tooth edged leaves, are up to 6 x 3.7 inches in size.
The foliage is gray-green.
The flowers are borne during late summer.
Hardy zones 6 to 10
Rhamnus frangula ( Alder Buckthorn )
A broadly spreading deciduous small tree to around 20 feet, that is native from Europe into western Russia, as well as northern Africa. It has escaped into the wild in the northeast U.S. and southern Canada and is invasive in some areas, especially moist woodlands.
Some records include: fastest recorded growth rate - 3 feet; 20 years - 27 x 17 feet; largest on record - 40 x 25 feet with a trunk diameter of 3 feet.
The smooth edged, oval to obovate leaves, are up to 4 x 2 inches in size.
The foliage is glossy deep green above, hairy light green beneath; turning to red in autumn.
The small, greenish, unisex flowers borne in axilliary clusters, during late spring. The flowers attract Honey Bees.
They are followed by fleshy berries, up to 0.5 inches, that are red ripening to black.
The gray bark is smooth with shallow, pale, vertical cracks.
Hardy zones 2 to 7 tolerating as low as -50 F in sun or shade. Young trees should be pruned to a single leader and feathered ( shortening and spacing branches ). Alder Buckthorn can be thinned and cut back hard during early spring. Deer resistant.
Asplenifolia
Reaching up to 15 x 12 feet, sometimes more, with fine textured, threadlike foliage.
Columnaris
Vigorous, tall and narrow; it is great for hedging. Some records include: 10 years - 13 x 4 feet; largest on record - 23 x 6.5 feet.
Fineline
A moderate growing, narrow, upright, columnar shrub, reaching up to 15 x 5 ( rarely over 11 x 4 ) feet, that combines the upright habit of Columnaris with the feathery foliage of Asplenifolia. It makes an excellent architectural plants, great for framing enterences and even for patio planters. It also makes a great narrow screen for townhouses and urban lots.
The finely dissected foliage is deep green, turning to brilliant orange-yellow during autumn. It produces very few fruits and is not invasive.
Hardy zones 2 to 7, tolerating as low as -50 F.
Latifolia
Very rare, native to the Azores. It is less cold hardy ( zone 7 est. ) but has much larger leaves, up to 5 x 3 inches.
Rhamnus glandulosa
Reaches up to 33 feet.
Leaves, up to 3 inches in length.
Rhamnus imeretina
A very attractive, spreading, deciduous shrub, reaching a maximum size of 12 x 15 feet, that is native to the Black Sea region.
The oblong leaves, are up to 14 x 6 inches in size.
The strongly veined foliage is dull green above, felted light green beneath, turning to bronze-purple in autumn.
The greenish unisex flowers borne in axilliary clusters, during summer.
They are followed by fruit that ripens to black.
Hardy zones 5 to 9. Shade tolerant.
Rhamnus infectoria ( Avignon Berry )
A dense handsome shrub reaching a maximum size of 15 x 15 feet, that is native from southern Europe to Iran.
The deciduous leaves are up to 1.5 x 0.7 inches in size.
Hardy north to zone 7
Rhamnus leptophylla ( Narrow Leaved Buckthorn )
A small tree native to China.
Some records include: 10 years - ; largest on record - 34 x 32 feet with a trunk diameter of 1.6 feet.
Rhamnus prionoides ( South African Dogwood )
A handsome, very dense, spineless, medium size, evergreen tree native to mountains of tropical Africa and those of eastern South Africa. The roots are not aggressive to it can be used in confined areas.
Some records include: 10 years - ; largest on record - 33 x 15 feet.
The leaves, are up to 4 x 2 inches in size.
The strongly veined, leathery foliage is very glossy deep green above, light olive green beneath.
The small creamy flowers borne in the leaf axils clusters, spring into early summer.
They are followed by small red berries that ripen to black.
Hardy zones 9 to 11.
Rhamnus pumila
A beautiful groundhugging deciduous shrub native to mountains of Europe.
It has excellent potential as groundcover, especially on commercial sites.
Some records include: 10 years - ; largest on record - 5 feet
The finely toothed, elliptic to rounded leaves, are up to 2.3 inches in length.
The fruits, up to 0.3 inches, are black.
Rhamnus purshiana ( Cascara )
An open, medium size, deciduous tree that is native to western North America from British Columbia;south to northern California to central Idaho & western Montana.
Some records include: fastest recorded growth rate - 2 feet; 10 years - ; largest on record - 70 x 60 feet with a trunk diameter of 3 feet; longest lived - 60+ years.
The finely toothed, broadly-elliptical leaves, are up to 8 x 3 inches in size.
The foliage is very glossy green.
The tiny yellow-green flowers borne in small axilliary clusters, during late spring.
They are followed by black fruits, up to 0.6 inches.
The smooth bark is gray-brown, with creamy colored stripes. The wood is heavy, weighing around 37 pounds per square foot.
Hardy zones 3 to 8 requiring 40+ inches of yearly average precipitation.
It grows in sun or shade and prefers moist soil. Thrives in the British Isles.
Propagation is from semi-ripe cuttings or seed.
* excellent video found on Youtube
Rhamnus saxatilis
A very twiggy, deciduous shrub, reaching a maximum height of 8 feet, that is native to central and southern Europe.
Some records include: 10 years - ; largest on record -
The toothed ovate leaves, are up to 2 inches in length.
The foliage is medium green.
The flowers are creamy-white.
They are followed by drupes that are red turning to black.
The side shoots are often tipped in spines.
Hardy zones
Rhamnus utilis
A deciduous large shrub to small tree, reaching a maximum height of 27 feet, that is native to China.
The tooth-edged, ovate leaves, are up to 6 x 3 inches in size.
The foliage is glossy deep green above, bright yellow-green beneath.
The flowers are yellowish-green, and are followed by a black berry.
Hardy zones 6 to 9
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