Wildflowers, Silk Oaks, Chamise, Buckwheat, and Agaves
San Diego's Coastal Wildflower Bloom continues practically unabated this year owing to late-season rains and cooler weather during April. On north-facing slopes and in shady canyon bottoms, where the sun's drying effects have not yet taken hold, look for native red monkeyflower, blue-eyed grass, wild hyacinth, and nonnatives such as chrysanthemum and mustard. Irrigated freeway embankments, with showy African daises, blooming ice-plant, and other forms of groomed landscaping, continue to exhibit brash coloration.
The Silk Oak Tree, a fast-growing import from Australia, comes into short-lived glory this month. Golden flower clusters decorate the silvery-green branches, an effect that is particularly stunning when seen in contrast to the blue-blossoming jacaranda trees often planted nearby. A common tree in San Diego-area parks, the silk oak is also a popular street and backyard tree in the older residential areas.
Chamise and Buckwheat, two of the most common native flowering plants in San Diego County's sage-scrub and chaparral plant communities, are in flower this month through June. Chamise, also known as greasewood, readily sprouts from root crowns after fire. Since the extensive wildfires of 2003 and 2007, much of the foothill and mountain regions of the county are again being smothered by this upstart, dominant type of drought-resistant vegetation. The stems of both chamise and buckwheat are tipped by clusters of small white or cream-colored flowers, fading to russet-brown by July. Near the coast look for flat-top buckwheat, common on south-facing slopes. Here it shares space with other low-growing sage-scrub plants like as black sage and California sagebrush.
Agaves, or century plants (Agave americana), have been sending up their asparagus-like flower stalks all over the San Diego area lately. In warm weather, the tips can rise as much as a foot a day. During summer big clusters of yellow and green flowers should appear on the tops of the stalks, some up to 30 feet tall. After the blooming cycle ends, the spine-tipped, fleshy daggers at the base of the stalk die (after a life of 10 or 20 years, not a century) and the stalk dries up, but suckers usually remain to continue a new cycle of growth, flowering, seed production, and death. The smaller desert agaves (Agave deserti), which are native to the western edge of the Anza-Borrego Desert, are now finishing their blooming cycle.