Alliaceae: Onion Family

Sierra Onion – Allium campanulatum

Blooms:

Mar–Oct

Plant Height:

16–30 cm

Flower Size:

Small

Origin:

Native

Habitat:

Dry mountain slopes above 600 m

Notes:

A comparatively small plant, with leaves that are usually withered by the time of flowering. The striking flowers are rose to purple, with a darker purple crescent at the base of each petal.

Crinkled Onion – Allium crispum

Blooms:

Mar–May

Plant Height:

15–35 cm

Flower Size:

Medium

Origin:

Native

 Habitat:

Heavy soil on inland hills

Notes:

Distinguished by the toothed, curled (“crisped”) margins of the inner petals.  The deep rose-purple flowers are in open umbels.  It has 2 or 3 leaves, which are shorter than the stem.

Hickman’s Onion – Allium hickmanii

Blooms:

Mar–May

Plant Height:

5–17 cm

Flower Size:

Medium

Origin:

Native

Rare or endangered

Rare – 1b.2

 Habitat:

Moist grassland near coast

Notes:

This is usually much smaller than its reported maximum 17 cm, and can be challenging to spot in long grass.  Petals are white to pink, about equal in size.   It has1 or 2 narrow leaves, often longer than the stem.

Three-cornered Onion – Allium triquetrum

Blooms:

Mar–Apr

Plant Height:

10–40 cm

Flower Size:

Small

Origin:

Europe

Habitat:

Woodland, moist places

Notes:

This is a very common garden escape.  Distinguished by its bright white flowers, with a dark green stripe in the center of each petal.  The stem is sharply triangular.

One-leaved Onion – Allium unifolium

Blooms:

May–June

Plant Height:

10–80 cm

Flower Size:

Medium

Origin:

Native

Habitat:

Moist places

Notes:

Despite its name, this onion has 2–3 leaves, which are shorter than the stem. The inflorescence has 14–35 flowers, with pink or white petals.  The flowers are 11–15 mm long, with 6 ovary crests in 3 pairs, separated by a longitudinal ridge.