CEANOTHUS

* photo of unknown internet source



* No species of Ceanothus are poisonous, however some make better tea than others...I have listed them below.

All species fix soil nitrogen. Most species prefer deep, well drained soil that is dry during summer. Other than root rot which may occur on poorly drained sites, they are generally immune to insect pests or disease. Tip prune after blooming for more compact plants that are sturdier. In fact, spring bloomers can be cut to within the first few buds of the previous years growth immediately after blooming for a more compact habit. Ceanothus, also called Summer Lilac are rarely bothered by insect pests or disease. They are great for attracting butterflies.

Ceanothus americanus ( New Jersey Tea )
A small deciduous shrub that is the oddball hardy eastern U.S. native member of a much larger genus of plants which are mostly native to California ( often called Californian Lilac's there and are not related in any way to Syringa - Lilac ). It is native to sandy open woodlands of eastern North America ( from eastern Nebraska to northern Minnesota to northern Michigan to Grand Bend, Ontario to Huntsville, Ontario to Chalk River and Constance Bay Sandhills near Ottawa, Ontario to southeast Quebec to central Maine; south to central Texas to central Florida...it is mostly absent from the Haliburton highlands of Ontario ). In the Windsor/Essex County, Ontario region; it was abundant at Point Pelee, the Ohio shore and also at Detroit, Michigan during the 1800s. It is endangered in Maine and Quebec. Typically reaching around 3 feet; plants growing on excellent sites may reach up to 5 x 10 feet.
The ovate, green leaves up to 4 x 3 inches in size are very hairy below and also last late in autumn. The foliage turns greenish-yellow during autumn.
An excellent tea can be made from the foliage...immerse the leaves in boiling water, roll them over to break the cells open then ferment for 2o to 24 hours.
In summer the abundant, fragrant, dull white flowers are borne in dense clusters up to 4 inches in length, during early summer.
Hardy zones 3 to 8 in full sun to partial shade and is drought tolerant. The New Jersey Tea has a very deep taproot so plants should be planted while very small. While many of its relatives do not tolerate cutting back into bare wood; this species can be cut to ground in very early spring for renewal.
Propagation is from seed either sown upon ripening or stratified for 3 months at 35 F. It can also be propagated from semi-ripe cuttings and root cuttings.

* photo taken on 4th of July 2010 in Washington, D.C.

* photo of unknown internet source

* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photos taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

* photo taken on Aug 9 2018 in Ellicott City, MD

* photo taken on June 21 2021 in Columbia, MD

* photo taken on Aug 15 2021 in Columbia, MD

* photo taken on Sep 4 2021 in Columbia, MD

* photo taken on Aug 21 2023 in Columbia, MD

* photos taken on Sep 9 2023 in Ellicott City, MD

* photo taken on July 1 2024 in Columbia, MD

Ceanothus arboreus ( Catalina Mountain Lilac )
A fast growing, evergreen spreading large shrub to small tree that is native to the islands off the Southern California coast. Some records include: 5 years - 11.5 feet; 5 years - 10 x 10 feet; 10 years - 20 x 20 feet; largest on record - 33 x 33 feet with a trunk diameter of 1 foot.
The ovate leaves, up to 4 x 2.3 inches, are glossy deep green above, gray downy beneath.
The abundant, vivid blue flowers are borne in cluster, up to 6 inches in length, during spring.
Hardy zones 7 to 9. The foliage is burned at 15 F and the plant is cut to the ground at 0 F but often regrows. Drought tolerant.

* photo taken by Jean Pawek @ CalPhotos

'Trewithen Blue'
Reaches same size as regular Ceanothus arboreus.
Leaves up to 4 inches in length are about the same as Ceanothus arboreus.
The fragrant deep blue flowers are borne in clusters up to 6 x 2 inches in size, over a long season.
Hardy zones 8 to 10

Ceanothus caeruleus
A small tree, reaching around 17 x 17 feet, that is native to Mexico.
Some records include: 10 years - 8 x 8 feet; largest on record - 25 x 17 feet.
The leaves are up to 4 inches in length, are brown hairy beneath.
The fluffy, sky-blue flowers are borne in panicles, up to 6 inches in length, during summer and autumn.
Hardy zones 9 to 10.

* historic archive photos

Ceanothus cordulatus ( Mountain Whitethorn )
A fast growing, semi-evergreen to evergreen shrub, reaching a maximum size of 6.5 x 10 feet, that is native to high mountains in southern California. It makes a great groundcover in suitable climates.
The leaves, up to 1 inch in length, are gray. The fragrant, white flowers are borne on dense clusters during spring.
The older stems are whitish.
Hardy zones 5 to 7. Prefers high elevations where snow is plentiful.

* photos taken by Jean Pawek @ CalPhotos

Ceanothus crassifolius ( Hoary Leafed Ceanothus )
A moderate growing, dense, evergreen shrub, reaching a maximum size of 14 x 13 ( rarely over 12 ) feet, that is native to southern California.
The thick leaves, up to 0.5 inches long, are dull green above, woolly white beneath.
The showy pure white flowers are borne during mid-winter to mid-spring.
Hardy zones 7 to 10 ( with no damage at 12 F surviving as low as 0 F ) in full sun on well drained soil. Drought tolerant.

* photo taken by C.C. Buck @ USDA-NRCS PLANTS Database

Ceanothus cuneatus ( Wedgeleaf Ceanothus )
A moderate growing, dense, upright, medium-sized, evergreen shrub, reaching up to 12 x 12 feet, that is native from western Oregon to southern California. It can be trained as a small tree.
The small, oblong leaves, up to 0.5 inches, are deep green.
The abundant, showy white flowers are borne during late winter to mid-spring.
Hardy zones 6 to 10 ( tolerating -15 F or colder ). Very drought and heat tolerant. Deer resistant.

* photo of unknown internet source

* photo taken by Jean Pawek @ CalPhotos

* photo taken by http://www.nwplants.com

'Sierra Mt. Lilac'
Fast growing, reaching up to 10 x 10 feet with whitish-blue flowers borne during mid spring.
Hardy north to zone 6

Ceanothus cyaneus ( San Diego Ceanothus )
A very fast growing, evergreen small tree, reaching a maximum size of 22 x 15 feet.
Some records include: 6 years - 20 feet.
The leaves, up to 2.5 inches in length, are glossy bright green.
The intense blue flowers are borne in long stalked clusters, up to 14 inches in length, during early summer.
Hardy zones 8 to 9. Drought tolerant.

'Sierra Blue'
Hardier, with no damage at 5 F and leaf drop at 0 F.
It also grows slightly larger, up to 22 x 25 feet.

Ceanothus x delileanus
A strong growing, deciduous to semi-evergreen large shrub that is the hybrid between Ceanothus americanus & C. coeruleus.
Some records include: 5 years - 6 x 9 feet; largest on record - 17 feet.
The broadly-oval leaves, up to 3.2 inches in length, are glossy deep green.
Hardy zones 7 to 9, preferring full sun on light well drained site. There is potential to produce hardier cultivars as a seedling of this hybrid managed to thrive for 10 years at Ottawa, Ontario's Dominion Arboretum for 10 years before being killed by a severe winter in 1957. Prefers a warm site protected from excessive wind. Tolerant of coastal conditions and limey soil. During early spring - cut back to a basal framework or to within 4 inches of previous seasons growth. Propagation is from semi-ripe cuttings taken during summer.

'Henri Desfosse'
Similar to Ceanothus 'Gloire de Varsailles', but with larger broader leaves and larger flower panicles.
Fast growing, dense, and rounded; it can reach up to 6.5 x 10 feet in 5 years, eventually slightly larger.
The glossy deep green leaves are borne on deep red stems.
The abundant, intense mid-blue flowers are borne on clusters during late spring to mid autumn.
The flowers are followed by red fruits.
Hardy zones 6 to 9, it thrives in the hot humid Mid Atlantic and southeastern U.S. from Arkansas eastward.

Ceanothus dentatus ( Cropleaf Ceanothus )
A spreading evergreen large shrub, that is native to coastal central California. Some records include: 10 years - 10 x 10 feet; largest on record - 20 x 10 feet.
The oblong leaves, up to 1 inch in length, are glossy deep green above, gray woolly beneath.
The soft bright blue flowers are borne in panicles all summer long.
Hardy zones 7 to 9. It is not happy in humid climates.

Ceanothus diversifolius ( Pinemat )
An evergreen, groundcover shrub, reaching up to 1 x 6 feet, that is native to oak and pine forest in northern and central California.
The finely-toothed, oval to rounded leaves, up to 2 x 0.7 inches in size, are glossy bright green above, hairy blue-green beneath. The very pale to bright blue flowers are borne on short spikes during early summer. Hardy zones 8 to 9. Heat and drought tolerant.

* photos taken by Jean Pawek @ CalPhotos

Ceanothus fendleri ( Fendlers Ceanothus )
A fast growing, medium-sized, deciduous shrub, reaching a maximum size of 8 x 6 feet, that is native from Wyoming to South Dakota; south to southern Arizona to southern New Mexico. It is extinct in South Dakota. Some records include: largest on record - 8 x 6 feet.
The thick leaves, up to 1.5 inches long, are gray-green above, dense woolly beneath.
The white flowers are borne on thick axilliary clusters during early to mid-summer, often repeating later.
The reddish-brown stems are armed with thorns up to 1 inch long.
Hardy zones 5 to 7 in full sun on well drained soil. It does not tolerate hard pruning.

Ceanothus foliosus ( Wavy-Leaf Ceanothus )
A moderate growing, spiny, erect, evergreen shrub, reaching a maximum size of 16 x 8 feet, that is native to coastal regions of northern to central California. It typically lives about 30 years.
The toothed leaves, up to 0.7 inches in length, are glossy deep green.
The bright blue flowers are borne in heads, up to an inch wide, during early to late spring.
Hardy zones 7 to 10 requiring 24 inches or more of average yearly precip.
It thrives in full sun to partial shade. Tolerates clay and summer moisture.

'Berryhill'
A low, mounding form, reaching only 3 feet in height.

Ceanothus gloriosus ( Point Reyes Creeper )
A central coastal California native that forms a fast growing, carpeting, groundcover shrub. Some records include: largest on record - 3.5 x 17 feet.
The leathery, toothed, Holly-like leaves, up to 2 inches in length, are glossy deep green.
The rich blue flowers are borne in clusters during spring.
Hardy zones 7 to 9 ( freezing to ground at 2 F ) in full sun to partial shade on well drained soil. Clay tolerant. It is great for coastal areas and is more deer resistant than many species. Prune after flowering.

'Anchor Bay'
A dense, mounding groundcover form; reaching up to 2 x 12 feet with leathery glossy deep green foliage. It is great for covering steep slopes and to trail over walls.

'Emily Brown'
A cultivar of subsp 'exaltatus', reaching up to 4 x 10 feet.
The leaves are small and the very profuse, deep violet-blue flowers are borne during early to mid spring.
Tolerates as low as 5 F.

subsp. 'exaltatus'
An erect shrub reaching a maximum size of 13 x 8 feet. Snow tolerant.

'Heart's Desire'
A moderate growing, low, dense form, reaching up to 1 x 6 feet, that is great for use as a dense, weed smothering groundcover for sloes.
The powdery-blue flowers are borne on dense clusters during early spring.
Hardy to as low as 5 F. It is a great groundcover for dry shade under Oaks.

Ceanothus greggii ( Mojave Ceanothus )
A moderate growing, mounding, medium-sized evergreen shrub that is native to mountains of the southwestern U.S. Some records include: largest on record - 10 x 14 ( rarely over 6 ) feet.
The smooth-edged to toothed, broad-elliptic to oblong leaves, up to 0.7 x 0.4 inches in length, are glossy mid-green. The small white flowers are borne in clusters, up to 1.3 inches across.
The stems are gray.
Hardy zones 5 to 10 in full sun on well drained soil. It is tolerant of heat, wind and cold. It is among the few western Ceanothus(s) that are hardy in the northeast including Michigan.

* USDA-NRCS PLANTS Database

Ceanothus griseus ( Carmel Ceanothus )
A very fast growing, arching, rounded, large evergreen shrub, reaching a maximum size of 10 x 10 feet, that is native to the hills of central California.
The leaves, up to 2 inches in length, are glossy deep green above, gray beneath.
The bright lilac-blue flowers are borne during spring.
Hardy zones 8 to 10 ( tolerating as low as 10 F ) in full sun to partial shade on well drained soil. Drought, wind and salt spray tolerant. It is clay tolerant but doesn't appreciate summer irrigation. Pruning after flowering helps maintain a dense compact habit.

'Diamond Heights'
A clone originating from 'Yankee Point' with bold attractive glossy foliage that is golden-yellow and blotched deep green in the center. It is semi-dwarf, reaching a maximum size of 2 x 6 feet.
It makes a great groundcover for dry shade under Oaks.

subsp. 'Horizontalis' ( Carmel Creeper )
Low and spreading, reaching an average size of 2 x 7 feet. Some records include: 10 years - 8 inches x 10 feet; largest on record - 3 x 36 feet.
The ovate to rounded leaves, up to 2 inches in length, are glossy bright green.
The light blue flowers are borne in clusters up to 1 inch long, during early spring.
Hardy zones 8 to 10.

'Hurricane Point'
Very fast growing with a spreading habit.
Some records include: largest on record - 3 x 36 feet.
Hardy zones 8 to 10

'Kurt Zalnik'
Extremely dark blue flowers.
Some records include: largest on record - 3 x 15 feet.
Hardy zones 8 to 10

'Louis Edmonds'
A mounded shrub, reaching a maximum size of 12 x 25 ( usually half that or less ) feet.
The leaves are glossy bright green.
The flowers are borne in large clusters, up to 6 inches.
Hardy zones 8 to 10, it is killed to ground at 0 F.

'Santa Ana'
Spreading in habit, reaching a maximum size of 8 x 20 feet with deep blue flowers.
Hardy zones 8 to 10

'Yankee Point'
Fast growing and low spreading shrub, reaching a maximum size of 5 x 17 ( usually under 3 ) feet in size. Some records include: 3 years - 10 feet across.
The leaves, up to 1.5 inches in length, are glossy deep green.
The deep blue flowers borne on clusters up to 2 inches wide, during spring ( randomly at other times of the year ).
Hardy zones 8 to 10, the foliage tip burns at 20 F and the plant is killed at 0 F.

Ceanothus hearstiorum ( Hearst's Ceanothus )
A moderate growing, long-lived, extremely prostrate groundcover shrub, reaching a maximum size of 1 x 12 feet, that is native to the central California coast where it is endangered.
The oblong leaves, up to 1.3 inches in length, are deep green.
The mid-blue flowers are borne on clusters, up to 1 inch wide, during early spring.
Hardy zones 8 to 9 in full sun to partial shade. Clay and drought tolerant.

Ceanothus herbaceus ( Prairie Redroot )
A perennial, reaching up to 3 x 6 feet in size, that originates from a thick rootstock. It is native to dry prairies, sandy shorelines and open woods in central North America ( from southeast Montana to southern Manitoba to Dryden, Ontario to Thunder Bay, Ontario to Michigan's Upper Peninsula to Manitoulin Island to Temagami, Ontario along the Ottawa River to northern New York State; south to southeast New Mexico to northern Louisiana. It is extinct in the wild in Montana; endangered in New Mexico, Louisiana, lllinois, Indiana, Ohio, Kentucky, West Virginia, New York and Vermont. In Ontario, it is mostly found west of Lake Superior, Manitoulin Island, on the northern Bruce Peninsula, Pinery Provincial Park in Grand Bend. In the Windsor/Essex County, Ontario region; it occurred sporadically at Point Pelee as well as abundantly on the Ohio shore during the 1800s. The root systems can reach up to 15 feet deep, and the crown can resprout after fire.
The minutely-toothed, oblong leaves are up to 3 x 1.2 inch in size. The foliage is glossy bright green, turning to yellow during autumn.
The small, white flowers are borne on dense, rounded clusters, up to 0.7 inches wide. They appear at the stem tips during late spring into early summer.
Hardy zones 2 to 7 in full sun to partial shade on sandy or rocky, well drained soil. It is very heat and drought tolerant. It can tolerate poor soil as its roots fix nitrogen..

* photo taken by Clarence A. Rechenthin @ USDA-NRCS PLANTS Database

Ceanothus impressus ( Santa Barbara Ceanothus )
A rapid growing, bushy, dense, spreading large evergreen shrub, native to scrublands of southern California. Some records include: 10 years - 10 x 15 feet; largest on record - 20 x 20 ( rarely over 10 ) feet.
The aromatic, deeply-veined, oblong to rounded leaves, up to 0.5 inches in length, are glossy deep green.
The abundant, deep blue flowers are borne in small, dense clusters, up to 1 inch long, during mid to late spring.
Hardy zones 7 to 10 requiring 12+ inches of average yearly rainfall. It has no leaf damage at 15 F and freezes to ground but resprouts at 0 F. Prefers full sun on light well drained site. Prefers a warm site protected from excessive wind. Tolerant of coastal conditions and limey soil. Cut back side shoots after flowering.
Propagation is from semi-ripe cuttings taken during summer.

'Vandenburg'
Fast growing, dense and mounded in habit, reaching up to 6 x 6 feet in 5 years, eventually larger.
The leaves are tiny and crinkled.
The abundant, deep blue flowers are borne in small, dense clusters during mid to late spring.
Hardy zones 7b+ ( tolerating as low as 5 F ).
Extremely drought tolerant.

Ceanothus incanus ( Coast Whitethorn )
A bushy spreading, medium sized, evergreen shrub, reaching around 10 x 11 feet, that is native to forested foothills in coastal mountains of northern California.
Some records include: largest on record - 13 x 15 feet.
The ovate leaves, up to 2.5 inches in length, are gray-green.
The small, slightly fragrant, white flowers are borne in dense clusters, up to 3 inches in length, during late spring into early summer.
The branches are somewhat thorny.
Hardy zones 7 to 10 preferring full sun on light well drained site. Prefers a warm site protected from excessive wind. Tolerant of coastal conditions and limey soil.
Cut back side shoots after flowering.
Propagation is from semi-ripe cuttings taken during summer.

Ceanothus integgerimus ( Deerbrush )
A fast growing, upright, rounded, medium-sized, semi-evergreeen to evergreen shrub, reaching a maximum size of 15 x 13 feet, that is native to mountain pine forests in the western U.S. ( from south-central Washington State; south to northern Arizona to central New Mexico; south to the Mexican border.
The broadly-ovate to rounded leaves, up to 3.2 inches in length, are glossy mid-green. The leaves make a great tea.
The showy, abundant, white to pale blue are borne on dense panicles, up to 6 inches long, during late spring.
Hardy zones 6 to 7 ( tolerating -10 F ) in full sun to partial shade on very well drained soil. It requires a mountain climate and a yearly precip. above 18 inches. It is highly drought tolerant.

* photos taken by Jean Pawek @ CalPhotos

* photo taken by C. Ray Clar and the Marian Koshland Bioscience and Natural Resources Library

* photo taken by Albert Everett Wieslander and the Marian Koshland Bioscience and Natural Resources Library

Ceanothus leucodermis ( Chaparral Whitethorn )
A moderate growing, dense, upright, evergreen shrub, reaching a maximum size of 13 x 15 feet. It makes a great screen.
The leaves, up to an inch in length, are blue-green.
The pale blue flowers are borne on mid-sized spikes from early to late spring.
Hardy zones 7 to 9, ( freezing to the ground at 0 F and root hardy to as low as -15 F ) in full sun on very well drained soil. It is very drought tolerant.

* photos taken by Jean Pawek @ CalPhotos

Ceanothus x lobbianus
The hybrid between Ceanothus dentatus & C. griseus.
Some records include: 10 years - 10 x 13 feet; largest on record - 15 x 15 feet.
The leathery, toothed, oblong leaves, up to 1 inch in length, are deep green above, pale green beneath.
The flowers are deep blue.
Hardy zones 8 to 10

Ceanothus maritimus ( Maritime Ceanothus )
A handsome, moderate growing, long-lived, groundcover shrub, reaching up to 3 x 8 feet in size, that is native to coastal California. The stems root as they grow. It is critically endangered in the wild.
The leathery, Holly-like leaves are very glossy deep green above, gray beneath.
The bright blue flowers are borne during spring.
Hardy zones 7 to 9 ( tolerating 0 F ) in full sun to partial shade on well drained soil.
It thrives in coastal areas with clay soil ( does not like clay ) and even grows well in parts of the eastern U.S. Drought tolerant and is great for dry shade under Oaks.

* photo taken by Jean Pawek @ CalPhotos

'Popcorn'
Abundant white flowers but otherwise similar.

Ceanothus megacarpus ( Big-Pod Ceanothus )
A fast growing, upright, medium-size evergreen shrub, reaching a maximum size of 15 x 15 ( rarely over 13 x 10 ) feet, that is native to southern California.
The leathery, oblong leaves, up to 1.3 inches in length, are deep green above, pale green beneath.
The abundant white flower spikes appear during winter to early spring.
Hardy zones 7 to 10 in full sun on well drained soil. It is very drought tolerant due to its deep roots.

Ceanothus oliganthus ( Hairy-leaf Ceanothus )
A very fast growing, large, evergreen shrub, reaching a maximum size of 17 x 13 ( rarely over 12 ) feet, that is native from northern California to the Baja Peninsula.
The leaves, up to 1.5 inches in length, are glossy bright green.
The mid-blue flowers are borne mid-winter to mid-spring.
Hardy zones 7 to 9 in sun to partial shade on well drained soil. Drought and clay tolerant.

Ceanothus x pallidus

'Marie Blue'
Compact in habit, reaching up to 3 x 4 feet.
The misty blue flowers are borne during late spring.
They are followed by showy red seed heads.
Hardy zones 6 to 8.

'Marie Simon'
A deciduous shrub, reaching up to 3.8 x 4.3 feet in 3 years and an eventual maximum size of 8 x 8 feet, bearing rose-pink flowers.
The attractive stems are red.
Hardy zones 6a to 10 in full sun to partial shade.
Deer resistant.

'Perle Rose'
A bushy, mounded, deciduous shrub, reaching up to 5 x 5 feet in 5 years and a maximum size of 13 x 8 ( rarely over 6 ) feet.
The broadly-oval leaves are glossy mid-green, turning yellow and persisting late in autumn.
The tiny pink flowers are borne in dense racemes during mid summer into early autumn. The flowers are borne on current seasons growth.
Hardy zones 6 to 8, preferring full sun on light, well drained site. Prefers a warm site protected from excessive wind. Tolerant of coastal conditions and limey soil, this is among the few Ceanothus that thrive in the eastern U.S..
During early spring - cut back to a basal framework or to within 4 inches of previous seasons growth.
Propagation is from semi-ripe cuttings taken during summer.

* photos taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

Ceanothus palmeri

* photo taken by Albert Everett Wieslander and the Marian Koshland Bioscience and Natural Resources Library

Ceanothus papillosus ( Wartleaf Ceanothus )
A fast growing, evergreen shrub, reaching a maximum size of 17 x 15 feet, that is native to coastal central and southern California.
The narrow leaves, up to 2 x 0.5 inches, are rough, glossy mid-green.
The rich blue flowers are borne early to late spring.
Hardy zones 8 to 10 with no damage at 5 F. Drought tolerant. Ceanothus parvifolius ( Little-leaf Ceanothus )

* photos taken by Jean Pawek @ CalPhotos

Ceanothus pinetorum ( Kern Ceanothus )

Ceanothus prostratus ( Squaw Carpet )
A moderate growing, creeping, evergreen shrub shrub, reaching a maximum size of 1.5 x 10 + feet. It makes a great groundcover and develops both a taproot and deep fibrous root system.
The toothed, oval to rounded leaves, up to 1 x 0.5 inches, are deep green.
It abundantly bears bright blue flowers on clusters up to 1 inch across during spring.
Hardy zones 5 to 8 in sun to partial shade on acidic soil with excellent drainage. It thrives in the eastern U.S. only where summers are cool. It hates heat and requires snow cover in winter. It thrives in dry shade under oak woodland.

* photo taken by Robert H. Ruf @ USDA-NRCS PLANTS Database

* photo taken by Albert Everett Wieslander and the Marian Koshland Bioscience and Natural Resources Library

* photo taken by Jean Pawek @ CalPhotos

* photo taken by http://www.nwplants.com

* historic archive photo

Ceanothus pumilus

Ceanothus purpureus ( Holly-leaf Ceanothus )
A fast growing, evergreen shrub, reaching a maximum size of 7 x 10 ( averaging 3 x 5 ) feet.
The spine-toothed, leathery leaves, up to 1 inch in length, are glossy deep green.
The deep blue flowers are borne late winter to mid-spring.
Hardy zones 7 to 9 requiring 12 + inches of average yearly precip.

Ceanothus rigidus ( Monterey Ceanothus )
A very fast growing, dense spreading shrub. Some records include: 10 years - 4 x 6.5 feet; largest on record - 13 x 17 feet.
The toothed, wedge-shaped leaves, up to 1.5 inches in length, are glossy deep green.
The purple-blue flowers are borne in dense heads, up to 1.3 inches in length, during late winter to early spring.
Hardy zones 8 to 10 tolerating as low as 10 F. Heat tolerant and extremely drought tolerant.

* photo taken by Jean Pawek @ CalPhotos

'Sierra Snow'
White flowers; otherwise similar.

Ceanothus sanguineus ( Redstem Ceanothus )
A vigorous, rounded, medium-sized, deciduous shrub, reaching up to 10 feet in height, that is native to pine forests and clearings in western North America ( from Terrace, British Columbia to Revelstoke, British Columbia to western Montana; south to northern California to Idaho; also found in the Black Hills of SD and Isle Royale in Michigan ).
The minutely-toothed, broadly-ovate leaves, up to 4 inches in length, are luxuriant mid to deep green above, paler beneath. The leaves make an excellent tea.
The very fragrant, white to pale pink flowers are borne on abundant, dense clusters up to 5 inches in length, during mid-spring to mid-summer.
The stems are purplish-red.
Hardy zones 5 to 7 ( seed source from northern Michigan likely much hardier ) in full sun to partial shade on sandy, well drained soil.

* photo taken by http://www.nwplants.com

Ceanothus spinosus ( Greenbark Ceanothus )
A fast growing, evergreen, large shrub to small tree, reaching a maximum size of 20 x 15 ( rarely over 10 ) feet in size, that is native to southern California. It is great for screening. The oval leaves are glossy bright green.
The fragrant, bright blue flowers are borne during spring.
It is slight to moderately spiny. The bark is green.
Hardy zones 8 to 10 in full sun on well drained soil. Clay, drought and severe pruning tolerant. DO NOT water during summer. Requires 20 + inches of yearly rainfall.

* photo of unknown internet source


Ceanothus thyrsiflorus ( Blueblossom )
A fast growing, small evergreen tree, native from California to Mexico. Some records include: 20 years - 23 x 33 feet; largest on record - 41 x 40 feet with a trunk diameter of 1.5 feet.
The oblong leaves, up to 2.3 inches in length, are glossy deep green.
The fragrant, pale blue flowers are borne in large clusters, up to 6 inches in length, during spring.
Hardy zones 7 to 9 in full sun to partial shade on light, well drained soil. Very drought and clay tolerant, it is also tolerant of occasional deep summer watering. Cut back side shoots after flowering. Pruning back stem tips after flowering will encourage a denser habit. Remove dead wood any time of year.
Propagation is from semi-ripe cuttings taken during summer.

* photos taken by http://www.nwplants.com

* historic archive photo

* photo taken by Albert Everett Wieslander and the Marian Koshland Bioscience and Natural Resources Library

'Oregon Mist'
Very fast growing, reaching up to 10 feet in 3 years, with tiny glossy deep green leaves, up to 0.3 inches in length.
The intense blue flowers are borne profusely during spring and fall, then sporadically for the rest of the year.
Developed by Xera Plants Inc., it is among the hardiest of all C. thyrsiflorus cultivars, it is hardy north to zone 7a having originated from wild plants at the far northern limit of its natural range in Coos County.

'Repens'
A very fast growing, dense, spreading to mounding groundcover form, that is native to coastal scrub in northern California. Some records include: 5 years - 3.3 x 8 feet; 10 years - 6.5 x 10 feet; largest on record - 6.5 x 17 feet ( typically lower in habit, not exceeding 3.5 feet ).
The broad elliptical leaves are glossy deep green.
The tiny, bright blue flowers are borne in dense, rounded racemes, up to 3 inches long, during late spring into early summer.
Hardy zones 7 to 10, tolerates windy coastal conditions.

'Skylark'
A fast growing, domed shrub, reaching up to 6.5 x 5 feet in 5 years, eventually to 7 x 7 feet. The deeply-veined leaves are glossy deep green.
The very fragrant, mid-blue flowers borne abundantly during late spring then sporadically over a long season lasting into early autumn.
Hardy zones 8a ( 7 on protected sites ) +

* photos taken by Milan Havlis, owner of central Europe's premier plant nursery

'Snow Flurry'
Very fast growing, reaching up to 18 x 20 + feet, with glossy rich green foliage contrasting with abundant, pure white flowers borne on large sprays.
Hardy zones 8b+

Ceanothus tomentosus ( Woollyleaf Ceanothus )
A fast growing, upright, rounded, evergreen shrub, reaching a maximum size of 13 x 12 feet, that is native to mountains of central and southern California.
The minutely-toothed, oval leaves, up to 1.3 inches in length, are glossy deep green, woolly beneath.
The white to blue flowers are borne on abundant spikes, up to 2.3 inches in length, during spring.
Hardy zones 7 to 9 ( with no damage at 0 F ) in full sun to partial shade on well drained soil. Drought tolerant.

* photo of unknown internet source


Ceanothus veitchianus
A fast growing, evergreen shrub reaching a maximum size of 13 x 13 feet, that is the hybrid between Ceanothus rigidus & C. thyrsiflora. Some records include: 5 years - 6.5 x 6 feet; 10 years - 8 x 8 feet.
The wedge-shaped leaves, up to 1 inches in length, are glossy deep green above, downy gray-green beneath.
The profuse deep-blue flowers are borne in clusters, up to 2 inches across, during early summer.
Hardy zones 6 to 9 surviving even further north into zone 4 as a perennial.

* historic archive photo

Ceanothus velutinus ( Tobacco Bush )
A deeply-rooted, moderate growing, evergreen ( in mild climates ), large shrub ( rarely small tree ) that is native to open pine woods in western North America ( from Smithers, British Columbia to Revelstoke, British Columbia to extreme southwest Alberta to north-central Montana to South Dakota; south to central California to Colorado ).
Some records include: fastest recorded growth rate - 2 feet; 5 years - 7 feet; largest on record - 20 x 33 feet; longest lived - 50 years.
The finely-toothed, broadly-elliptical leaves, up to 3 x 2 inches, are glossy deep green above, velvety beneath. The leaves make a great tea.
The white flowers are borne in dense panicles, up to 5 inches long, during mid-summer.
Hardy zones 3 to 8 in full sun to partial shade, preferring cool summers but can tolerate extreme heat. It is rarely bothered by insects or deer

* photo of unknown internet source

* photo taken by Jean Pawek @ CalPhotos

* photo taken by Jean Pawek @ CalPhotos

* photos taken by Sheri Hagwood @ USDA-NRCS PLANTS Database

* photo taken by Albert Everett Wieslander and the Marian Koshland Bioscience and Natural Resources Library

HYBRIDS
More hybridizing should be done to produce cold hardy blue flowering Ceanothus.

* photos of unknown internet source




Ceanothus 'A.T. Johnson'
A vigorous, evergreen shrub, reaching a maximum size of 13 x 11 feet.
The leaves, up to 1.3 inches in length, are glossy green above, gray downy beneath.
The profuse, fuzzy, rich blue flowers are borne in clusters, up to 2.5 inches in length, during spring, often repeating during autumn.
Hardy zones 8 to 10

Ceanothus 'Autumnal Blue'
A vigorous, bushy, medium-size, evergreen shrub, reaching a maximum size of 10 x 10 feet. Some records include: 5 years - 6.5 x 6.5 feet.
The broadly oval leaves are glossy bright green.
The abundant, sky-blue flowers are borne in panicles, up to 3.2 inches in length, from late summer into autumn, often also during late spring.
Hardy zones 6 to 10 in full sun on light well drained site. Prefers a warm site protected from excessive wind. Tolerant of coastal conditions and limey soil. Cut back side shoots after flowering.
Propagation is from semi-ripe cuttings taken during summer.

Ceanothus 'Blue Buttons'
A spreading, large, evergreen shrub, reaching a maximum height of 17 feet.
The powdery-blue flowers are borne in clusters during late spring.
Hardy zones 8 to 10

Ceanothus 'Blue Cascade'
Some records include: first year - 12 feet; largest on record - 40 feet.
The leaves, up to 2 x 0.5 inches, are deep green.
The mid blue flowers are borne in clusters, up to 3 inches across.
Hardy zones 8 to 10

Ceanothus 'Blue Cushion'
A compact, arching, evergreen shrub, reaching a maximum size of 6.5 x 8 feet.
The flowers are pale blue.
Hardy zones 7 to 10

Ceanothus 'Blue Jeans'
An evergreen shrub, reaching a maximum size of 10 x 10 ( rarely over 5 ) feet. Some records include: 5 years - 6.5 x 5 feet.
It makes a great informal hedge.
The small, Holly-like leaves are up to 1.5 inches in length.
The vivid medium blue flowers are borne early to mid spring.
The flowers contrast well with Tete a Tete Daffodil.
Hardy zones 7b to 10 tolerating at least as low as 0 F, thriving in the Pacific Northwest.

Ceanothus 'Blue Mound'
A medium-sized evergreen shrub, reaching a maximum size of 5 x 8 feet. Some records include: 5 years - 5 x 6.5 feet.
The finely-toothed leaves are are glossy green.
The bright blue flowers are borne in dense clusters, up to 3 inches in length, during late spring into early summer, often repeating late summer into autumn.
Hardy zones 8 to 10

Ceanothus 'Burkwoodii'
The hybrid between Ceanothus floribundus & C. Indigo'.
A bushy, dense, evergreen shrub, reaching a maximum size of 10 x 10 feet. Some records include: 5 years - 5 x 5 feet.
The oval leaves, up to 1.3 inches in length, are glossy green above, gray beneath.
The bright blue flowers are borne in clusters, up to 2.3 inches in length, during late summer into autumn.
Hardy zones 8 to 10

Ceanothus 'Cascade'
An evergreen large shrub or small tree. Some records include: 5 years - 6.5 x 6.5 feet; largest on record - 27 x 12 feet.
The leaves are up to 2 inches in length.
The bright blue flowers are borne in clusters, up to 3.2 inches in length, during spring.
Hardy zones 8 to 10

Ceanothus 'Celestial Blue'
Some records include: largest on record - 10 x 13 feet.
It can flower up to 10 months of the year.
Hardy zones 7 to 10 tolerating as low as 0 F.

Ceanothus 'Centennial'
A fast growing, creeping, low, evergreen shrub, reaching up to 2 x 10 ( averaging 0.5 x 5 ) feet, that is the hybrid between Ceanothus foliousus & C. griseus. It is valuable as a dense, weed smothering groundcover and also for trailing over walls.
The attractive, tiny leaves, up to 0.5 inches long, are glossy deep green.
The flowers are intense mid to deep blue. They are borne on clusters, up to 2 inches long, during early summer.
Hardy zones 8a+, requiring a Mediterranean climate with a dry summer. It tolerates clay and dry shade and makes a great groundcover for under oaks.

Ceanothus 'Concha'
A fast growing, dense, arching, spreading, evergreen shrub, reaching a maximum size of 23 x 27 ( rarely over 10 x 12 ) feet. Some records include: 5 years - 8 x 8 feet. It is a hybrid between Ceanothus impressus & C. papillosus.
The narrow leaves are up to 2 inches in length, are glossy deep green.
The abundant, deep blue ( lavender in bud ) flowers are borne in clusters, up to 1.5 inches long, during mid to late spring.
The flowers are red in bud.
Hardy zones 8 to 10 tolerating as low as 0 F. It prefers little or no summer water.

* historical archive photo

Ceanothus 'Dark Star'
A very fast growing, spreading, evergreen shrub, reaching a maximum size of 8 x 12 feet. Some records include: 5 years - 6.5 x 6.5 feet.
The tiny leaves, up to 0.5 inches in length, are glossy deep blackish-green.
The fragrant, intense deep blue flowers are borne late winter to early spring.
Hardy zones 7b to 10 ( tolerating as low as 5 F ), preferring little or no summer water. Thrives in the Pacific Northwest if planted against a warm south facing wall.

Ceanothus 'Delight'
The hybrid between Ceanothus papillosus & C. rigidus.
A large, evergreen shrub, reaching 10 x 10 feet in 10 years and a maximum eventual size of 17 x 17 feet.
The ovate leaves, up to 1 inch in length, are deep green.
The bright blue flowers are borne in long panicles, up to 4 inches in length, during spring.
Hardy zones 7 to 10

Ceanothus 'Edinburgh'
A clone of an upright form of Ceanothus griseus.
A vigorous, bushy, upright, evergreen shrub, reaching 8 x 10 feet in 10 years and a maximum size of 13 x 13 feet.
The leaves, up to 3 inches in length, are olive green.
The rich deep blue flowers are borne in clusters, up to 2 inches in length.
Hardy zones 8 to 10

Ceanothus 'Edwardsii'
A fast growing, tall evergreen shrub.
The leaves are glossy, deep green above, light green beneath.
The deep blue flowers are borne in dense clusters during late spring.
Hardy zones 8 to 10

Ceanothus 'Frosty Blue'
A very fast growing, dense, upright, large, evergreen, shrub, reaching a maximum size of 10 x 12 feet. It typically lives around 15 years.
The leaves are up to 0.5 inches in length, are very glossy, mid-green.
The abundant, mid-blue flowers are borne in clusters, up to 4 inches in length, during spring.
Hardy zones 8 to 10 tolerating as low as 0 F. Clay tolerant.

Ceanothus 'Gentian Plume'
A fast growing, spreading, evergreen large shrub to small tree, reaching a maximum size of 25 x 30 feet.
The deep blue flowers are borne in large open panicles during spring, often repeating during autumn.
Hardy zones 8 to 10

Ceanothus 'Gloire de Versailles
A cultivar of Ceanothus x delileanus, forming a vigorous, bushy, deciduous shrub.
Some records include: 10 years - 6.5 x 6.5 feet; largest on record - 14 x 8 feet.
The broadly-oval leaves, up to 5 x 4 ( rarely over 3 inches ) in size, are mid-green.
The showy powdery blue flowers are borne in dense, large clusters, up to 8 inches in length, from mid-summer into autumn.
Hardy zones 7 to 10 tolerating as low as 0 F, preferring full sun on light well drained site. Prefers a warm site protected from excessive wind, it is among the few Ceanothus that thrive in the hot humid southeastern U.S. Tolerant of coastal conditions and limey soil.
During early spring - cut back to a basal framework or to within 4 inches of previous seasons growth.
Propagation is from semi-ripe cuttings taken during summer.

* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken @ U.S. Botanical Garden, Wash., DC on Oct 21 2014

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

Ceanothus 'Italian Skies'
A variety of Ceanothus foliosus.
A fast growing, medium size, evergreen shrub, reaching a maximum size of 5 x 12 feet. Some records include: 10 years - 5 x 8 feet.
The small leaves, up to 0.7 inches in length, are glossy deep green.
The bright blue flowers are borne in branched inflorescences, up to 6 inches in length.
Hardy zones 8 to 10, the foliage may be damaged below 10 F but is quick recovering during spring.

Ceanothus 'Joyce Coulter'
A fast growing shrub, reaching a maximum size of 6 x 13 ( rarely over 5 x 8 ) feet.
Long lived, it can survive for more than 20 years.
The toothed leaves, up to 2 inches in length, are glossy deep green.
The blue flowers are borne in large clusters, up to 5 inches in length, during spring.
Hardy zones 8 to 10. No damage at 8 F; frozen at 0 F.
Tolerant of heat and drought, fire and clay.

Ceanothus 'Julia Phelps'
A moderate growing, upright, dense, medium-sized, evergreen shrub, reaching a maximum size of 12 x 13 feet.
The leaves, up 1 inch in length, are deep green.
The purplish red buds open to indigo blue flowers during spring.
Hardy zones 7 to 10 ( tolerating as low as 0 F ) preferring coastal climates.

Ceanothus 'Ken Taylor'
A cultivar of Ceanothus thyrsifolius var repens, which it is very similar to except for the blooms which are lilac-blue.
Hardy zones 8 to 10

Ceanothus 'Pin Cushion'
A dense, compact arching shrub, reaching a maximum size of 7 x 7 feet.
The leaves,up to 2.5 inches in length, are deep green.
The flowers are deep blue.
Hardy zones 8 to 10

Ceanothus 'Puget Blue'
A dense large shrub, reaching a maximum size of 10 x 10 feet. Some records include: 2 years - 6 feet; 5 years - 7 x 7 feet ( avg ).
The leaves are up to 0.8 inches in length.
The deep blue flowers are borne in clusters, up to 2 inches in length, late spring into summer.
Hardy zones 8 to 10

Ceanothus 'Ray Hartman'
The hybrid between Ceanothus arboreus & C. griseus. A fast growing, long lived, somewhat weeping, evergreen large shrub to small tree, reaching a maximum size of 20 x 25 feet.
Some records include: 2 years - 20 feet. Its life expectancy is around 20 or more years.
The large leaves, up to 6 inches in length, are glossy deep green.
The dark blue flowers are borne in clusters, up to 6 inches in length.
Hardy zones 8 to 10, severe damage at 0 F, death at -5 F. Protect young plants from deer damage. It requires 13 + inches of yearly rainfall.

Ceanothus 'Southmead'
A bushy, dense, medium-sized, evergreen shrub, reaching up to 5 x 5 feet in 5 years, rarely much larger.
The finely-toothed, oblong leaves, up to 1.3 inches in length, are glossy deep green, light green beneath.
The very deep blue flowers are borne late spring into early summer.
Hardy zones 8 to 10

Ceanothus 'Tilden Park'
A fast growing, dense, bushy, evergreen shrub, reaching a maximum size of 8 x 6.5 feet.
The small, narrow leaves are glossy green.
The very abundant, lilac-blue flowers are borne on sprays up to 4 inches in length, during mid to late spring.
Hardy zones 7a+ in full sun to partial shade. Tolerant of ocean salt breezes.

Ceanothus 'Topaz'
A vigorous, compact, semi-evergreen shrub, reaching up to 5 x 5 feet in 5 years and a maximum size of 10 x 10 ( rarely over 8 ) feet. it originated from a hybrid between Ceanothus delilianus & pallidus.
The broad leaves, up to 3 inches in length, are deep green.
The indigo-blue flowers are borne early summer until autumn frost.
The flowers are borne on new wood.
The flowers are followed by attractive red seedheads.
Hardy zones 6 to 10. Very tolerant of seashore conditions.
Prune after blooming.

Ceanothus 'Tuxedo'
A very unusual, upright, rounded shrub, reaching a maximum size of 8 x 10 feet, that is a hybrid between C. americana & C. thyrsifolia.
The deep black, ovate foliage ( up to 1.8 x 1.6 inches in size ) contrasts very well with the lavender-blue flowers borne in inflorescences up to 2.3 x 1.5 inches in size, during late summer and autumn.
Hardy zones 7a+ ( tolerating 0 F )

Ceanothus 'Victoria'
Also called Ceanothus impressus 'Victoria'. A fast growing, dense, upright, rounded, evergreen shrub, reaching up to 6 x 6 feet in 10 years with an eventual maximum size of 9 x 12 ( rarely over 8 ) feet. It can be sheared as a hedge.
The deeply-veined, ovate leaves, up to 1.3 inches in length, are very glossy, very deep green.
The bright bluish-purple flowers are borne profusely during early summer then sporadically the rest of the season.
Hardy zones 7a to 10 ( tolerating 0 F but is possibly even hardier north to zone 6 against a protected south facing wall or if covered in cloth during the coldest part of winter ).

* photos taken by Milan Havlis, owner of central Europe's premier plant nursery

ADDITIONAL CULTIVARS

Ceanothus pallidus 'Marie Gold'
https://patents.google.com/patent/USPP25704P2/en?
https://www.soonerplantfarm.com/plant/ceanothus-marie-gold
Ceanothus 'Lemon Ice'
https://www.freepatentsonline.com/PP20938.html
Ceanothus griseus horizontalis 'Highlights'
https://patents.google.com/patent/USPP29321P3/en?
Ceanothus thyrsiflorus 'El Dorado'
https://www.freepatentsonline.com/PP13433.html
Ceanothus thyrsiflorus 'Cool Blue'
https://patents.google.com/patent/USPP24884P2/en?