PlantFiles: Splendid Mariposa
Calochortus splendens

Calochortus splendens is one of the more southernly species of the genus (not counting the mesoamericans in Section III) and can be found in the north in Colusa County, California, south down to Baja California Sur. The species is most common in San Diego County, although rapacious development is steadily eating away at it's preferred habitat: coastal sage and chaparral. It also occurs on the Santa Catalina and Los Coronados Islands. Northern growers are a robust 30~60 cm high, but those growing in Mexico are desert plants associated with Pachycereus, Fouquieria, and Agave, and are much smaller and sometimes lack nectaries. Mexican populations are threatened by over-grazing.

The typical flowers are a gorgeous violet. Inside the delicately unfurling cup are rich purple anthers on bright red filaments, all surrounded by a profusion of snow-white hairs (fungoid trichomes). The nectaries are sometimes marked with purple spots - these are easiest to see from the outside of the petals.

C. splendens is a member of Section II. Mariposa, Subsection 5. Venusti (Flowers campanulate and erect; sepals lanceolate obtuse-attenuate; petals obovate to cuneate; nectaries of varying shapes; capsules always erect, three-angled; seeds flattened and set horizontally in the capsule; bulbs with membranous tunics) (Callahan, "The Genus Calochortus" in "Bulbs of North America", Timber Press, 2001)

C. splendens is easily my favorite California wildflower. It used to be common in the foothills behind our house when I was growing up in San Diego (although I have never seen them in anywhere near the abundance described by another member.) I recall with horror now how as a child I used to go tramping through the sagebrush in mid-May gathering dozens of flowering stems to give to Mom. Needless to say, that kind of behavior is now circumscribed by California's laws. If in San Diego, Mission Trails Park is still a good place to see them - cross the San Diego River at the Old Mission Dam, and you can find them growing between the boulders. Calochortus weedii var. weedii also occurs higher up in the hills.

For the Ipai and Tipai bands of the Kumeyaay (Diegueño) peoples, the bulbs of C. splendens were an important foodstuff, adding to their staple of acorns. The bands practiced a rudimentary form of agriculture, setting fires to the underbrush, thus fertilizing the soil and creating clearings for Calochortus, Bloomeria, and Dichlostemma to thrive.

Dutch growers have selected and named a cultivar, Violet Queen. Though probably more garden-worthy than the species, I find the flower mediocre.

C. splendens is not as difficult to grow as some would have it - but it does take a lot of care. I grow mine in a mixture of half coarse sand, half granulated loam, with some granitic gravel mixed in. Some growers warn that the plant dislikes organic material in the soil. Above all, excellent drainage is neccessary.
I've had nearly 100% germination rates with fresh seed, but the percentage goes down the longer it is stored. Sow in late-September or October (when there is at least a 10C fluctuation in day and night temperatures) and keep moist until the first sprouts appear in 2~4 weeks. At this point caution is advised: the sprouts are very prone to damping off. Over the winter, I grow in clay pots in a plastic cold frame, so the temperature never goes below a few degrees C. This species is not hardy.
Most of the winter I water once or maybe twice a week at the most. I fertilize with bonemeal one or two times a month while in growth, or plant ash when I can get it. When flower spikes start to appear in April, start cutting back on water, and after the blooms have died back, keep dry.
Over-summering seems to be the biggest problem for most growers. Although SoCal summers are extremely hot and dry, Calochortus bulbs are deep enough in the soil to avoid cooking (unlike humans without air-conditioning ;) I store mine in the pot in the dark coolness under the house, and the Tokyo 99% humidity seems to keep the bulbs from drying out.
The flowers are self-compatible and will set copious seed if hand-pollenated.

I heartily recommend this plant for the North-American Wildflower enthusiast who is willing to put in a little extra time and effort.

C. splendens is widespread in San Diego county. A field of them nodding in the breeze is a lovely sight. There are a half dozen other species of calochortus here, some quite rare. all beautiful. My favorite is C. concolor, the Golden Mariposa Lily followed by C. alba and C. dunnii. WTH - San Diego.