Have you ever seen a century plant bloom? If not, put it on your horticultural bucket list! Century plant is a common name for a number of species of agave (Agave sp.), usually Agave americana in South Carolina. Most agaves are monocarpic, meaning that an individual plant only flowers once in its life and then dies. In fact, the name “century plant” is a much-exaggerated reference to the long time it takes for the plant to flower. In SC, agaves generally require 10 to 15 years to grow large enough to bloom.
In the summer of 2018, a giant agave (Agave salmiana) planted in 2005 bloomed in my Easley, SC backyard. It was a spectacle that lasted for months and intrigued friends, family, and social media. I first noticed that a bloom was imminent when a spike began to emerge in mid-March from the center of the rosette (spiraled leaf cluster). The spike grew incrementally taller until it reached about 15 feet by mid-April. Interestingly, Agaves are members of the asparagus family (Asparagaceae), a kinship that can be seen in early stages of the agave flower spike which resembles an asparagus spear on steroids.
By the end of April, the spike began to branch at the top into what’s known as a panicle inflorescence. A large cluster of flower buds was held at the end of each branch. In late-May individual yellow, tubular flowers began to open on the lowest branches and progressed up the panicle throughout June. Scores of insects and hummingbirds visited the nectar laden flowers and by the end of June thousands of flowers had opened and faded. Afterwards, the panicle slowly died followed by the rosette which withered to a crumpled heap. It’s hard to imagine a more spectacular end to a plant’s life!
Fortunately, before agaves flower they usually produce offsets or “pups.” These offsets can be transplanted or left in place to succeed their mother and grow until their own exuberant end. And the cycle repeats. As you drive around SC this summer, keep your eye out for flowering agaves. They aren’t super common but are worthy of admiration!
The bloom spike of this Agave salmiana appeared in March 2018, emerging from the center of the plant’s rosette. Cory Tanner, ©2018, Clemson Extension
In mid-April the bloom spike reached 15 feet tall and resembled a giant asparagus spear.
Cory Tanner, ©2018, Clemson Extension
Cory Tanner, 6’ 4” tall, stands with the agave in late-April as the flower spike began to branch into a panicle.
Cory Tanner, ©2018, Clemson Extension
Agave flowers beginning to open on the bottom of the fully branched panicle.
Cory Tanner, ©2018, Clemson Extension
A cluster of agave flowers as seen from above. Some have just opened and extended their anthers (male, pollen-bearing parts).
Cory Tanner, ©2018, Clemson Extension
Agave approaching full bloom in June 2018.
Cory Tanner, ©2018, Clemson Extension
