Calochortus pulchellus aka Mt. Diablo Fairy Lantern

Calochortus pulchellus is a bulbous plant in the lily family, Liliaceae. Its common names include golden star tulip and pretty-flowered Mariposa lily. It comes from Mount Diablo in Contra Costa County, northern California. Its native range is small, rather than spread across the state. It grows on wooded and brush-covered slopes above 656 feet [200 metres]. Its habitats include chaparral and forests of pine and oak. Kew places it within a temperate climate.

This plant grows to about 1 foot [0.3 metres] tall. Its bulb lies below ground and supports its seasonal growth. Plants For A Future gives June as its flowering month. Each flower has both male and female organs. Insects pollinate the flowers. The supplied species records give no details of leaf shape or fruit. They also give no mature spread or flower colour.

Good drainage is a key need in cultivation. Use deep, fertile, sandy soil, or a mix with much grit. Sandy and loamy soils both suit it when water drains freely. It accepts mildly acid, neutral, and mildly alkaline soil. Grow it in sun or light shade. A bulb frame offers a more controlled growing site. Plants For A Future also suggests trying a sheltered south-facing wall. It lists sites beside east-facing walls as another option.

Care needs change with the plant's growth cycle. Give it ample moisture while it grows, then keep it very dry after flowering. The source also stresses dry winter conditions. Cold alone poses less trouble than wet soil in British gardens. Plants For A Future lists USDA zones 3–7, but calls British cultivation difficult. This makes careful control of moisture more important than the zone rating alone. Young bulbs can rot if their resting conditions stay too wet. They can also fail if allowed to dry out fully.

Sow ripe seed promptly, or sow in early spring under a cold frame. Use a mix that drains very freely. Seeds may take one to six months to sprout at 15°C. Leave seedlings in place through their first two growing years. The first dormant period needs close care to avoid losses. Plants For A Future records the small bulbs as edible, raw or cooked. It lists no known hazards or medicinal uses. That hazard statement does not establish safety for pets.