Phacelia viscida

Phacelia viscida, commonly known as Sticky Phacelia or Tacky Phacelia, is an annual herb belonging to the borage family, Boraginaceae (formerly placed in Hydrophyllaceae). It is native to California in the United States and Baja California in Mexico. The species name "viscida" is Latin for "sticky," referring to the glandular hairs that cover the plant and give it a characteristic sticky feel.

Description

Phacelia viscida is an erect annual herb typically growing to a height of 10 to 60 centimeters (4 to 24 inches). The stems are generally unbranched or sparsely branched and are covered in short, glandular hairs that exude a sticky resin, giving the plant its common name.

Leaves: The leaves are alternate, petiolate, and range from ovate to lanceolate in shape. They are often deeply lobed or toothed, especially the lower leaves, while upper leaves may be less divided. Like the stems, the leaves are also covered in glandular, sticky hairs.

Flowers: The inflorescence is a scorpioid cyme, characteristic of many species in the Boraginaceae family, where flowers uncoil as they bloom. The flowers are bell-shaped, typically vibrant blue, purple, or sometimes lavender, and are often darker in the throat. Each flower has five petals and five prominent stamens that protrude from the corolla. Blooming occurs primarily from March to July.

Fruit: The fruit is a small, ovoid to globose capsule containing several seeds.

Taxonomy

Phacelia viscida was first described by George Bentham. It is part of the genus Phacelia, which comprises about 200 species, mostly native to western North America. The genus Phacelia was historically placed in the family Hydrophyllaceae, but modern phylogenetic analyses (such as those by the Angiosperm Phylogeny Group) have subsumed Hydrophyllaceae into an expanded Boraginaceae.

Distribution and Habitat

Sticky Phacelia is endemic to California and Baja California. In California, it is primarily found in the southern and central coastal regions, extending into the western Transverse and Peninsular Ranges. Its preferred habitat includes:

• Chaparral
• Coastal sage scrub
• Grasslands
• Disturbed areas, such as roadsides and clearings

It typically grows in dry, open areas on sandy or rocky soils, often at lower elevations.

Ecology

Like many Phacelia species, Phacelia viscida flowers are attractive to various pollinators, including bees and other insects, which are drawn to its nectar and pollen. The sticky exudate may serve as a defense mechanism against small herbivorous insects.

Cultivation

While not widely cultivated, Phacelia viscida can be grown in gardens in its native range, particularly in naturalized or wildflower settings. It thrives in full sun and well-drained soil and is drought-tolerant once established. Its striking blue-purple flowers and distinctive sticky foliage make it an interesting addition to native plant gardens.