Allium howellii
A tall, California-endemic Allium with a reddish-brown bulb, a single cylindrical leaf, and a leafless scape bearing an umbel of up to 100 lavender-to-white flowers on granite and serpentine soils, in the Amaryllidaceae family and first described in 1938 by Eastw.
Common Names
Howell's Onion, Clokey's Onion, San Benito Onion
Summary
Howell's onion is a California-native perennial herb that grows from a bulb and reaches a stem to about 15–60 cm tall. It has simple leaves and an umbel inflorescence of 10–100 flowers; each flower is 5–8 mm with a white to pale lavender perianth, and an ovary bearing six obvious, irregularly dentate crests. The bulb measures 9–17 mm and is ovoid to nearly spherical, and flowering occurs from April to June.
Native to California, it occurs in mountainous habitats on granite and serpentine soils.
Lifecycle
Perennial
Height
20-24 inches
Hardiness Zones
Zones 7a-10b
Sunlight Requirements
Ideally full sun; tolerates partial shade.
Soil Type
Granitic and serpentine soils that are well-drained
Soil Drainage
Well-draining soil
Bloom Color
White to lavender, including pale lavender, with pink also reported
Bloom Time
Spring to Summer
Foliage Color
Yellow leaves
Fall Foliage Color
Yellow
Leaf Lifecycle
Deciduous
Growth Rate
2x growth (doubling in size)
Seasons of Interest
Spring and Summer
Propagation Methods
Seeds, Division
Attracts Wildlife
Attracts bees and butterflies
Taxonomy
- Taxonomic Rank
- Species
- Author
- Eastw.
- Publication
- Leafl. W. Bot. 2: 109 (1938)
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Angiosperms
- Order
- Asparagales
- Family
- Amaryllidaceae
- Genus
- Allium
Inferior Taxa
Allium howellii var. howellii Allium howellii var. sanbenitense