The Desert Garden at the Huntington Botanical Gardens in San Marino is celebrating its 100th birthday this year. Here, visitors photograph part of the collection of 500 golden barrel cactuses, some 85 years old. (Glenn Koenig / LAT)
A variegated Agave attenuata, with its broad, smooth leaves, stands out in the gardens muted palette. (Glenn Koenig / LAT)
Slender Pachycereus marginatus, or pipe organ cactus, tower above a rock-strewn bed of flowering specimens, creating a natural fence. (Glenn Koenig / LAT)
A bank of brilliant red blooms rise from Aloe arborescens, from the original plantings selected by the gardens first superintendent, William Hertrich. (Glenn Koenig / LAT)
Rows of prickles line the spear-like leaves of an aloe plant in the Desert Garden, which has more than 250 aloe species. (Glenn Koenig / LAT)
The white floss silk tree is native to South America and has a heavy trunk studded with thick spines. (Glenn Koenig / LAT)
A moving lens appears to set a bed of golden barrel cactuses in motion. (Glenn Koenig / LAT)
Visitors follow the paved path through the pincushion rockery, a 150-foot-long planting of mammillaria cactuses dating to 1929. (Glenn Koenig / LAT)
Bright pink flowers dot the wispy, hair-like surface of Mammillaria hahniana in winter and early spring. (Glenn Koenig / LAT)
