Jacaranda mimosifolia

Blue Jacaranda
Conservation status
Vulnerable  (IUCN 2.3)
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Lamiales
Family:	Bignoniaceae
Genus:	Jacaranda
Species:	J. mimosifolia
Binomial name
Jacaranda mimosifolia D.Don

The Blue Jacaranda, Jacaranda mimosifolia more often known simply as the "Jacaranda", is a sub-tropical tree native to South America that has been widely planted elsewhere because of its beautiful and long-lasting blue flowers. Older sources give it the systematic name Jacaranda acutifolia, but it is nowadays more usually classified as Jacaranda mimosifolia. It is also known as the Black Poui, or as the fern tree. In scientific usage, the name "Jacaranda" refers to the genus Jacaranda, which has many other members, but in horticultural and everyday usage, it nearly always means the Blue Jacaranda.

Habitat

The Blue Jacaranda has been cultivated in almost every part of the world where there is no risk of frost; established trees can however tolerate brief spells of temperatures down to around −7°C (20°F). In the United States, it grows in parts of Oregon, California, Nevada, Arizona, Texas, and Florida., and has been reported to grow in Lafayette, southern Louisiana, the Mediterranean coast of Spain, in southern Portugal (very noticeably in Lisbon), southern Italy (in Naples there are beautiful specimens). It is regarded as an invasive species in South Africa and Queensland, Australia, the latter of which has had problems with the Blue Jacaranda preventing growth of native species. Lusaka, the capital of Zambia also sees the growth of many Jacarandas.

J. mimosifolia flowers

J. mimosifolia fruits

A jacaranda seed pod, before falling.

Appearance

The tree grows to a height of 5 to 15 metres (16 to 49 feet). Its bark is thin and grey-brown in colour, smooth when the tree is young though it eventually becomes finely scaly. The twigs are slender and slightly zigzag; they are a light reddish-brown in colour. The flowers are up to 5 cm long, and are grouped in 30 cm panicles. They appear in spring and early summer, and last for up to two months. They are followed by woody seed pods, about 5 cm in diameter, which contain numerous flat, winged seeds. The Blue Jacaranda is cultivated even in areas where it rarely blooms, for the sake of its large compound leaves. These are up to 45 cm long and bi-pinnately compound, with leaflets little more than 1 cm long.

In the USA, 30 miles east of Los Angeles where winter temps can dip to 10 degrees F (-12 C) for short several-hour periods, the mature tree survives with little or no visible damage. Sapling survival is unknown to this writer. This tree can be invasive into septic (sewer) systems and can raise concrete slabs or damage foundations if planted within 20-30 feet (6-9 meters) of these structures. Profuse flowering is considered quite messy where some have complained the flowers can leave stains if left on vehicle surfaces. The large single-trunked specimen I examined was about 30 feet (9 meters) tall and spread some 25 feet (7.6 meters) at the canopy with a trunk about 12-15 inches (30-40 cm) diameter. Seed pods can be a mess to clean up. However, some have gathered the pods, cleaned and decorated the unusually shaped, tough pods for use on Christmas trees and other decorating ideas. Some pods will be "3-winged" and are especially choice for decorating. The pods will be about 2 to 3 inches (5-7.5 cm) across.

Taxonomy

The taxonomic status of the Blue Jacaranda is unsettled. ITIS regards the older name, Jacaranda acutifolia, as a synonym for J. mimosifolia. However, some modern taxonomists maintain the distinction between these two species, regarding them as geographically distinct: J. acutifolia is endemic to Peru, while J. mimosifolia is native to Bolivia and Argentina. If this distinction is made, cultivated forms should be treated as J. mimosifolia, since they are believed to derive from Argentine stock. Other synonyms for the Blue Jacaranda are Jacaranda chelonia and J. ovalifolia. The Blue Jacaranda belongs to the section Monolobos of the genus Jacaranda.

Tree in flower

Jacaranda trees in Bhutan

Popular culture references

Pretoria, the administrative capital of South Africa is popularly and poetically known as Jacaranda City or Jakarandastad in Afrikaans because of the huge number of the trees which turn the city blue when they flower in the spring. The name Jakarandastad is frequently used in Afrikaans songs, such as Staan Op by Kurt Darren.

People in Australia sing a Christmas song about Jacaranda trees, as the blooms are only seen in summer time—as the song explains, "When the bloom of the jacaranda tree is here, Christmas time is near" ...

In Argentina, writer Alejandro Dolina, in his book Crónicas del Ángel Gris ("Chronicles of the Gray Angel"), tells the legend of a massive jacarandá tree planted in Plaza Flores (Flores Square) in Buenos Aires, which was able to whistle tango songs on demand. María Elena Walsh dedicated her Canción del Jacarandá song to the tree. Also Miguel Brascó's folk song Santafesino de veras mentions the aroma of jacarandá as a defining feature of the littoral Santa Fe Province (along with the willows growing by the rivers).

British singer songwriter Steve Tilston eulogizes the beautiful blue tree he encountered in Australia with his song "Jacaranda" (track 11 on his album Ziggurat, 2008).

Medicinal uses

Water extract of Jacaranda mimosifolia shows higher antimicrobial action against Bacillus cereus and Escherichia coli than gentamicin sulfate does. The extract also acts against Staphylococcus aureus.

Gallery

• 
  leaves in Hyderabad, India.
• 
  flowers in Hyderabad, India.
• 
  fruits in Hyderabad, India.
• 
  trunk in Hyderabad, India.
• 
  May 2010, Martin County, Florida

See also

• South Australian suburbs

References

External links

• Template:IUCN2006 Listed as Vulnerable (VU B1+2ac v2.3)
• Blue Jacaranda among plants growing well around San Antonio, Texas