Tuesday, 21 April 2015

Agave- The Century Plant

Agave- The Century Plant

I was fortunate enough to spot this Agave plant flowering in the Etobicoke Greenhouse one day. They had taken pains to create a hole in the glass roof to allow the plant to grow freely. 

Now, why would they go through this much trouble, I inwardly queried. 

Intrigued, my brief investigation revealed that this particular plant was special indeed. Also known as an 80 year-old American plant, they only flowered once then died. 

Surreptitiously about this time an article from the CBC caught my attention:

“Housed at the University of the Michigan since 1934, the plant has grown so rapidly since the spring that at more than 27 feet (8.2 metres) it is now too tall for the Ann Arbor conservatory, which has had to remove a pane of glass to accommodate it. The sudden spurt is a sign that the plant could bloom soon. The variegated American agave (Agave americana) was collected in Mexico by famed ethno-botanist Alfred Whiting, who then was a University of Michigan graduate student. Known as the century plant because it blooms infrequently, it is native to Mexico and the American Southwest and typically lives 10 to 25 years in the wild before blooming a single time then dying.” ” (University of Michigan/Matthaei Botanical Gardens/Associated Press)

How fortunate for us that we had the very same plant flowering right in our back yard. Naturally I wanted to learn more. Here’s some brief info I gathered from Wikipedia:

Agave is a genus of monocots. The plants are perennial, but each rosette flowers once and then dies. Some species are known by the name century plant. The genus is placed in the subfamily Agavoideae of the broadly circumscribed family Asparagaceae. It’s composed of e about 208 species.

Common names include century plant, maguey (in Mexico), or American aloe (it is not, however, closely related to the genus Aloe). The name "century plant" refers to the long time the plant takes to flower. The number of years before flowering occurs depends on the vigor of the individual plant, the richness of the soil, and the climate; during these years the plant is storing in its fleshy leaves the nourishment required for the effort of flowering.

In the variegated forms, the leaf has a white or yellow marginal or central stripe. As the leaves unfold from the center of the rosette, the impression of the marginal spines is conspicuous on the still erect younger leaves. The plants require protection from frost. They mature very slowly and die after flowering, but are easily propagated by the offsets from the base of the stem.

They are succulents with a large rosette of thick, fleshy leaves, each ending generally in a sharp point and with a spiny margin; the stout stem is usually short, the leaves apparently springing from the root. Along with plants from the related genus Yucca, various Agave species are popular ornamental plants. 

It is a common misconception that agaves are cacti. They are not related to cacti, nor are they closely related to Aloe whose leaves are similar in appearance.

Each rosette is monocarpic and grows slowly to flower only once. During flowering, a tall stem or "mast" grows from the center of the leaf rosette and bears a large number of short, tubular flowers. Once the flower blooms it will take many months before the plant dies. 

But in the plant's final throes, it is expected to produce "pups," or genetic clones that look the same as the parent plant, from which they can propagate the species. In addition there is another way to propagate this plant…For after development of the fruit when the original plant dies, suckers are frequently produced from the base of the stem that of which can become new plants.

Chiefly Mexican, agaves are also native to the southern and western United States and central and tropical South America.

Agave Americana, or a century plant, was introduced into Europe probably by Spanish and Portuguese explorers about the middle of the 16th century. It became popular in Europe during the 19th century, when many types were imported by collectors and it became widely cultivated as an ornamental plant. 

Blue A. Americana occurs in abundance in the Karoo, and arid highland regions of South Africa. Introduced by the British settlers in 1820, the plant was originally cultivated and used as emergency feed for livestock. Today it is used mainly for the production of syrup and sugar.

Agave’s uses are numerous:

The bruised leaves, for instance, have afforded a paste from which paper was manufactured. Its juice was fermented into an intoxicating beverage, pulque, of which the natives, to this day, are extremely fond. 

Its leaves further supplied an impenetrable thatch for the more humble dwellings. Thread, of which coarse stuffs were made, and strong cords, was drawn from its tough and twisted fibers. 

Pins and needles were made from the thorns at the extremity of its leaves, and the root, when properly cooked, was converted into a palatable and nutritious food. 

There are four major parts of the agave that are edible: the flowers, the leaves, the stalks or basal rosettes, and the sap. Each agave plant will produce several pounds of edible flowers during its final season. 

The stalks, which are ready during the summer, before the blossom, weigh several pounds each. Roasted, they are sweet and can be chewed to extract the aguamiel, like sugarcane. 

When dried out, the stalks can be used to make didgeridoos. The leaves may be collected in winter and spring, when the plants are rich in sap, for eating. During the development of the inflorescence sap rushes to the base of the young flower stalk. 

Agave nectar (also called agave syrup), a sweetener derived from the sap, is used as an alternative to sugar in cooking, and can be added to breakfast cereals as a binding agent. Meanwhile the leaves also yield fiber. Agave Americana for instance is the source of pita fiber, and is used as a fiber plant in Mexico, the West Indies and southern Europe.

The Navajo similarly found many uses for the agave plant. A beverage is squeezed from the baked fibers, and the heads can be baked or boiled, pounded into flat sheets, sun dried, and stored for future use. The baked, dried heads are also boiled and made into an edible paste, eaten whole, or made into soup. The leaves are eaten boiled, and the young, tender flowering stalks and shoots are roasted and eaten as well. The fibers are used to make rope, the leaves are used to line baking pits, and the sharp pointed leaf tips are used to make basketry awls.

The juice from many species of agave can cause acute contact dermatitis. It will produce reddening and blistering lasting one to two weeks. Episodes of itching may recur up to a year thereafter, though the rash is no longer visible. Irritation is, in part, caused by calcium oxalate raphides. 

The agave, in short, was meat, drink, clothing, and writing materials for the Aztec! Surely, never did Nature enclose in so compact a form so many of the elements of human comfort and civilization!

Such a find! I wasn’t about to let this opportunity slip by so I made periodic trips to the greenhouse and took some pictures as the flowering progressed to seed. 

In August we went back and took these photos of the plant after the staff had removed the dead parts.

The End


  1. Wow! I have two of these growing in my front yard in Chula Vista ca. They are approx. 6-7 feet tall and are putting out flowers. They also are attracting a lot of june bugs and hummingbirds :). I was wondering, what I should do with the stem when all the flowers fall off. You mentioned that the plant dies? Both of these are approx. 4-5 years old. can I cut the stem off? The flowers are falling all over the side walk and are making quite a mess also.
    Also, they are putting out quite a few suckers which are popping up all over. They sure are a site to look at.
    Thank you for all the information.

    1. Sorry about the delay.
      We went back to the greenhouse this month and they had removed the original plant down to the roots and left the new runners. I'll see if I can add the two pictures.