Cycads and palms look alike in many respects, but they are not related. Their physical resemblance caused early confusion about their botanical relationship. The longtime association of these plants led Victorian era collectors to create cycad and palm gardens similar to the one displayed here. These plants are also represented in the Garden’s geographic collections.
Palms and cycads are found in tropical, subtropical, and warm temperate regions of the world. This collection includes palms and cycads from warm temperate zones. The plants in this cycad and palm garden demonstrate the wide variety of species that can be successfully cultivated in the Bay Area’s mediterranean climate.
Cycads are dioecious, meaning that each plant is either female or male. Female cycads produce cones containing large, brightly colored seeds with a fleshy, outer covering that attracts birds, fruit bats, and rodents. In the process of consuming the fleshy coverings, the seeds are dispersed. Cycads are slow to reproduce and limited in distribution.
The Garden’s cycads are one of four cycad collections recognized by the Plant Collections Network (formerly the North American Plant Collection Consortium); recognition by the PCN comes close to conferring national status on public garden collections. The Garden’s collection is very broad, containing all the recognized genera of cycads worldwide. This collection has a particular strength in the genus Encephalartos from southern Africa, including a number of very endangered species. The Garden is focused on this collection’s conservation importance, and is working to establish a breeding program for these plants in collaboration with fellow PCN gardens and collaborators in South Africa.
Palms exhibit many features that are not typical of trees. For most of their lives they grow taller, not wider, with no branches and no annual rings. A palm’s xylem and phloem run from its roots to its leaves in scattered strands. Unlike broadleaved trees and conifers, there is no cambium layer to divide the xylem and phloem into concentric cylinders. There is no cambium producing new cells, so there’s no thickening of the trunk or roots and no tree rings are formed.