Ceratozamia mexicana, or Mexican Horncone, is just one of two species in the genus Ceratozamia. The trunks of this species will with great age reach up to 4-6 feet (1.21-1.82 m) tall and about 12 inches (60 cm) in diameter. The whorled pinnate leaves are erect to spreading and gracefully arched. The leaves can be from 3-9 feet (0.9-2.7 m) long with narrowly to broadly lanceolate pinnae 4-16 inches (10-40 cm) long. I estimate our specimen to be about 70 years old. They are very slow growers and are hardy in the landscape in USDA zone 10-11.
Blooming: Plants are either female or male. The reproductive structures are borne on modified, scale-like leaves which densely group together to form large cones. With this species and most cycads, the female will produce cones without pollination, but the seed will not mature or have embryos. Our plant produces a cone every year but we do not have a male plant to cross it with. (If you know where we can obtain pollen, please let us know!)
Culture: Ceratozamia mexicana needs light shade with a well drained soil mix. We grow our plant under 25% shade at all times. Our plant has been grown in a large concrete container for many years. The soil in the container is basically loam and sand in equal parts, with large gravel added to insure good drainage. The plant receives ample water all year long and is fertilized monthly with a balanced fertilizer. During the winter months, water is somewhat restricted, but care is taken not to let it dry out too much.
Propagation: Ceratozamia mexicana is propagated by the removal of offsets and from seed.
Ceratozamia mexicana was featured as Plant of the Week October 12-18, 2007.
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Cal's Plant of the Week was provided as a service by the University of Oklahoma Department of Microbiology & Plant Biology and specifically Cal Lemke, who used to be OU's botany greenhouse grower and an avid gardener at home as well. If the above links don't work, then try the overview site. You may also like to look at the thumbnail index. ©1998-2012 All rights reserved.