Whitethorn Ceanothus (Cordulatus)

The Whitethorn Ceanothus (Cordulatus) is generally described as a perennial shrub. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The Whitethorn Ceanothus (Cordulatus) has green foliage and inconspicuous white flowers, with an abuncance of conspicuous brown fruits or seeds. The greatest bloom is usually observed in the early summer, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The Whitethorn Ceanothus (Cordulatus) has a long life span relative to most other plant species and a slow growth rate. At maturity, the typical Whitethorn Ceanothus (Cordulatus) will reach up to 8 feet high, with a maximum height at 20 years of 4 feet.

The Whitethorn Ceanothus (Cordulatus) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by bare root, container, seed. It has a moderate ability to spread through seed production and the seedlings have medium vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -23°F. has high tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Mountain whitethorn can be used for ground cover on slopes, terraces or steep banks and as a barrier plant. Mountain whitethorn may be allowed to assume natural forms or may be shaped through pruning and pinching off the growing tips.

General Characteristics

Buckthorn Family (Rhamnaceae). Mountain whitethorn is a densely branched, spiny, evergreen, flat-topped native shrub, which reaches heights of 2 to 5 feet. However, at elevations, such as the Lake Tahoe Basin, it assumes a low spreading growth form. Individual plants may spread to form continuous ground cover over areas with a diameter up to 12 feet. The numerous stems terminate in a hard sharp point thus, the name whitethorn.

Whitethorn flowers form in a small, dense cluster 1 to 2 inches long. The flowers, which bloom from late spring to mid summer, have a heavy penetrating fragrance. During the flowering season, the abundant white flowers may cause areas to appear covered with snow.

Required Growing Conditions

California, Nevada, and Southwest Oregon. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Adaptation Mountain whitethorn is well suited to dry open flats and rocky slopes with well-drained soils.


General Upkeep and Control


Plant Basics
Growth Rate Slow
General Type Shrub
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Early Summer
Displays Fall Colors No
Shape/Growth Form Multiple Stem
Drought Tolerance High
Shade Tolerance Intolerant
Height When Mature 8
Vegetative Spread None
Flower Color White
Flower Conspicuousness Yes
Fruit/Seed Abundance High
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Moderate
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Seed
Moisture Requirements Low
Cold Stratification Required No
Minimum Temperature -23
Soil Depth for Roots 20
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability Yes
Responds to Coppicing No
Growth Requirements
pH Range 7–8.5 pH
Precipitation Range 16–16 inches/yr
Planting Density 682–2728 indiv./acre
Soil Textures Coarse, Medium
Soil Depth for Roots 20
Minimum Frost-Free Days 90 day(s)
Salinity Tolerance Low
CaCO3 Tolerance High
Sustainability & Use
Leaf Retention No
Palatability High
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database, plants.usda.gov.
National Plant Data Center, Baton Rouge, LA 70874-4490 USA