Agave americana

Agave americana. Although the typical age of A. americana is 30 years, it is thought that our A. americana shown in this photo was over 50 years old when it produced its flower stalk in 2019.  Photo by Terri Greene, Oct17-2016

Although it's nicknamed the century plant, the longevity of Agave americana is typically 30 years as opposed to 100 years as the name suggests

The flower stalk of Agave americana, which the plant sends up at the end of its life, is an impressive structure reaching up to 30 feet tall and covered with yellow flowers. After pollination occurs, the main plant begins to produce seeds and forms plant shoots at its base. After flowering, the main plant will die, leaving the plants that formed around its base to replace it until they mature and the process repeats itself. Plants that flower only once and then die are referred to as monocarpic.

A. americana is a chiropterophilous plant. Chiropterophilous means "bat loving" (derived from Chiroptera, the name of the scientific order to which bats belong). In its native habitat of Mexico and the southwestern U.S., the A. americana's blooms are mainly pollinated by bats.

This is one of several Agave species that can be used in making tequila-like liquor. (True tequila is produced from Agave tequilana, commonly called blue agave.) The nectar from the plant is marketed as a natural sugar with a low glycemic index due to its high fructose content.

Fibers within the leaves are used to make ropes and coarse fabric. A popular artisan technique in Mexico and Central America called piteado uses thread made from A. americana fibers to embroider designs onto saddles and leather accessories such as sandals, head bands, and belts.

Agave americana "swan song"

Our century plant (Agave americana) has bloomed. The species is monocarpic which means that it blooms once and then dies; thus, our plant has reached the end of its life (it's estimated to be over 50 years old).

It began sending up a flower stalk in March 2019. The stalk has grown to a height of at least 30 feet (which required removing a section of glass to let the stalk pass through the ceiling), producing horizontal branching near its top. Greenish-yellow flowers 3 to 4 inches in length bloomed in panicles (loosely branched clusters of flowers) at the branch ends.

The flower stalk was discovered bent over onto the greenhouse roof on July 22, 2019—most likely due to the previous night's storm and the stalk weakening as the plant dies. Greenhouse staff left the stalk on the roof for now to see whether some of the flowers will set seed.

Find the century plant in the central bed in Room D of the Jordan Hall greenhouse.

View the progress of the bloom . . .

Our Agave americana is sending up a flower stalk. Photo by Terri Greene, Apr04-2019
Mar27-2019: The flower stalk begins to emerge from the top of the plant. Photo by John Leichter, Mar27-2019
The stalk is straightening as it grows. Photos were taken one day apart on April 3 and 4. Photos by John Leichter, Apr03/04-2019
Apr08-2019: The 82-inch flower stalk is now about 3.5 feet above the top of the plant. It is less than 4 feet from the greenhouse ceiling. Photo by John Leichter, Apr08-2019
Apr12-2019: Our Agave americana's flower stalk is within 2 feet of the high point of the greenhouse ceiling. Photo by John Leichter, Apr12-2019
Apr15-2019: Our Agave americana's flower stalk continues to nose toward the peak of the greenhouse ceiling. A piece of the glass had been removed to allow the stalk to continue its growth upward; however, the stalk has shifted its direction slightly southward and away from the opening. Photo by John Leichter, Apr15-2019
Apr17-2019: The flower stalk has pushed upward beyond the roof of the greenhouse. The stalk is approximately 12.5 feet. Photo by Terri Greene, Apr17-2019
Apr26-2019: Agave americana flower stalk viewed from inside the greenhouse and from the outside. Photo by John Leichter, Apr26-2019
Apr30-2019: Greenhouse gardener John Leichter took this photo of the Agave americana early this morning. The flower stalk extends at least 3 feet beyond the roof. Photo by John Leichter, Apr30-2019
May20-2019: The horizontal branches have begun to appear near the top of the stalk, which now extends approximately 7 feet about the roof line. Greenish-yellow flowers 3 to 4 inches in length will bloom in panicles (loosely branched clusters of flowers) at the branch ends. Photo by John Leichter, May20-2019
May28-2019: Flower buds are forming at the ends of the lateral branching. The main stalk continues to grow upward as well—now 26 feet from base to tip. Photo by John Lemon, May28-2019
Jun11-2019: The flower stalk measured 30 feet on June 6, 2019. We're still waiting for the buds to open. John Leichter, greenhouse gardener, captured this photo of the stalk and a little "rainbow" this afternoon. Photo by John Leichter, Jun11-2019
Jun24-2019: The Agave americana plant has begun to slump and its leaves to droop as the buds on its flower stalk are closer to opening. Photo by John Leichter, Jun24-2019
Jun26-2019: A closer look at the Agave americana buds. Photo by Roger Hangarter, Jun26-2019
Jul05-2019: The Agave americana buds have begun to open.  Photo by Terri Greene, Jul05-2019
Jul08-2019: More buds have opened as can be seen in the photo of the full stalk extending above the greenhouse roof (right). Look closely at the photo of the blooms to see the stamens and stigma of the individual flowers. Photos by Roger Hangarter, Jul08-2019
Jul18-2019: Reflection of the Agave americana's flower stalk on a wet walkway outside of the greenhouse. Photo by John Leichter, Jul18-2019
Jul22-2019: The combination of last night's storm and the plant withering most likely led to the flower stalk bending over onto the greenhouse roof. Photo by John Lemon, Jul22-2019