Plant in full sun in a light to medium well-drained soil where it is drought tolerant. Can tolerate temperatures down to at least 20° F and some claim to as low as 0° F so long as the soil is kept dry. Prune occasionally to keep dense or contain size. It is best to plant a bit away from pathways where one might find it dangerous, but it can be used as an unusually attractive and impressive barrier plant that nothing would dare go through.

Colletia paradoxa hails from Uruguay, western Argentina and south-eastern Brazil, where it most often is a woodland plant on scrubby dry hillsides. It is seen cultivated in botanical collections in mediterranean climate regions, but its hardiness has allowed it to be cultivated in the British Isles since 1824. Unfortunately, this once common plant is reportedly becoming less so in its native range due to habitat loss. The genus name coined by the French naturalist Philibert Commerson honors French botanist Philibert Collet (1643-1718). German born botanist Kurt Polycarp Joachim Sprengel described this species in 1825 with the specific epithet from the Greek words 'para' meaning "besides" and 'doxa' meaning "opinion" which combined to mean "against the usual opinion", "unexpected" or "strange" in refence to the interesting look of the plant. This species is considered synonymous with Colletia cruciata, a name used by William Jackson Hooker in 1829 to describe a plant discovered by Scottish naval surgeon and botanist Dr. John Gillies while he was in South America. Other common names include Crucifixion Thorn, Crucifix Thorn, Thorn of the Cross, Jet-Plane Plant, Gigs, Curumamil and Espina de la Cruz (Thorn of the Cross). Interestingly, the members of Colletia, including C. paradoxa, are able to fix atmospheric nitrogen into a usable form much like many legumes can do and this allows the plants to grow on nutrient poor soils.

This species was introduced into cultivation in California (as Colletia cruciate) by Dr. Francesco Franceschi (Emanuele Orazio Fenzi) in 1909. We have long admired this plant in the Desert Garden at the Huntington Gardens and also at the Berkeley Botanic Garden, where it was planted in 1949. We have grown this interesting plant since first getting seed from Seedhunt in 2007 - our current crops are from seed since collected from our own plants growing on the nursery grounds. 

This information about Colletia paradoxa displayed is based on research conducted in our horticultural library and from reliable online resources. We also will relate observations made about it as it grows in our nursery gardens and other gardens we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments that we receive from others and we welcome hearing from anyone with additional information, particularly if they can share any cultural information that would aid others in growing it.