Our century plant (Agave americana) has chosen 2012 for its final glorious act. After growing imperceptibly in our front yard for fifteen years, the agave has astounded us with The Stalk. This bloom stalk is the pinnacle of the plant’s lifetime. The century plant gathers steam for 10-30 years, growing slowly in a striking rosette form made up of grey green leaves that come to be 6 feet long. Each leaf carries a spiny margin and a hefty spike on the tip. In late March we noticed our agave was pushing up a huge woody stalk like an asparagus spear from a nightmare. The stalk grew at a remarkable rate; the authors of Plants for an Arid Landscape estimate the century plant produces 6-14 inches of growth per day. Just two weeks after we noticed the stalk the plant had more than tripled in height and added extra dazzle, generating horizontal arms loaded with flowers, or an inflorescence*. If we had wanted to produce the fermented drink pulque we would have cut the stalk before the bloom. This sends the sweet liquid known as honey water to the heart of the plant. The agave flowers are pollinated by hummingbirds, moths and bats. The fruits that set are capsules, which will turn brown and split open when mature, releasing 8-10 seed from each fruit. Millions of seeds may be produced by one plant. Our neighbors have an Agave americana that also chose to bloom this year, and we’ve had a little contest going to see whose gets tallest. In April we measured and to young James’s disappointment our stalk was in the lead. Since then our plant has added on and now measures 16 ½ feet. But apparently we are still in the minor leagues as agave stalks are known to grow 26 feet tall.
*Inflorescence – the reproductive portion of the plant that bears clusters of flowers in a certain pattern.
Sunset Western Garden
University of Texas Wildflower Center online at http://www.wildflower.org