Plant of the month: July
Also Known As: tequila agave or blue Weber agave
Native To: Mexico
Blooms: Inflorescence consists of a stalk (quiote) up to 5 metres (16 ft) high and topped with bunches of upright, yellow tubular flowers in summer.
Habitat: Favours altitudes of more than 1,500 metres (5,000 ft) and grows in rich and sandy soils in desert
Where Found At Birmingham Botanical Gardens: On Loudon Terrace, next to outdoor cacti and succulent display.
There are more than 200 species of Agave in the world. They all belong to the asparagus family (Asparagacecae) and their huge flower stems resemble an asparagus on steroids! In 1905, this species of Agave was classified by German botanist Franz Weber, from whom it took its common name. Only this species of Agave is suitable for the production of Tequila and is made from the distilled leaf juice. There are two categories of tequila. The first category is 100% Agave tequila made from only blue Weber Agave and the best tequila you can buy. It has the best taste and doesn’t produce a hangover! The label will simply state 100% agave and nothing else. The second category is a mixed or blended tequila which is made using a minimum of 51% blue Weber Agave and the remainder is mixed with sugar cane or corn sugars.
The flowers are pollinated in the wild by a native Mexican bat (Leptonycteris nivalis) which drinks the sugary nectar. After which the plant produces several thousand seeds per plant. So much energy is put into growing the huge flower spike that the whole plant dies (monocarpic). Offsets at the base of the plant, known as ‘pups’, together with the seeds produced by the flowers ensure future generations. The ‘pups’ on commercial plants are removed when about a year old to allow the parent plant to grow larger. The plants are then reproduced by planting these shoots; leading to a considerable loss of genetic diversity in cultivated blue agave.