Gilia Ruiz & Pav.

Gilia is an exclusively American genus and counts about 25 or up to 50 species, depending on species delimitation. They are centered in the southern United States and southern South America. Several, mostly similar-looking species are grown as annual ornamentals (e.g. Whiteley 2000, Jäger & al. 2008). They are particularly popular these days in wildflower seed mixtures.
The separation of the species with a capitate inflorescence is rarely straightforward. They all look very similar and several additional species and infraspecific taxa are also grown as ornamentals, e.g. G. capitata subsp. abrotanifolia (Green) Grant (Whiteley 2000). The latter has slightly longer corollas (7-13, vs. 5-8 mm) with oblong (vs. linear) lobes and acuminate calyx lobes (vs. acute lobes). It may have been overlooked.
A useful online key for the identification of Californian species of Gilia is provided by the e-Jepson Flora at:

1 Corolla pale lilac with much darker center. Flowers solitary or very few together, not in heads === Gilia tricolor
Corolla bluish (sometimes white in cultivars), without darker center. Flowers in many-flowered to relatively few-flowered heads, never solitary === 2

2 Inflorescence densely capitate. Corolla throat shorter than to as long as tube. Stamens reaching or exceeding corolla lobes === G. capitata
Inflorescence loosely capitate. Corolla throat usually longer than tube. Stamens included to reaching corolla lobes === G. achilleifolia


Brand A. (1907) Gilia. In: A. Engler (ed.), Das Pflanzenreich, Heft 27. Leipzig: 87–150. [available online at:]

Grant V. (1998) Classification of the genus Gilia (Polemoniaceae). Phytologia 84(2): 69-86. [available online at:]

Grant V. (2004) Taxonomy of the Polemoniaceae: Gilia and Lathrocasis. Sida, Contrib. Bot. 21(2): 531-546. [available online at:]

Grant V. & Day A.G. (1998) Transfer of some species from Gilia to Allophyllum and Tintinabulum, and the effects of the transfer on the generic definition of Gilia (Polemoniaceae). Phytologia 84(5): 368-382. [available online at:]

Grant A. & Grant V. (1956) Genetic and taxonomic studies in Gilia VIII. The cobwebby gilias. Aliso 3: 203–287. [available online at:

Grant A. & Grant V. (1960) Genetic and taxonomic studies in Gilia XI. Fertility relationships of the diploid cobwebby gilias. Aliso 4: 435–481. [available online at:

Ingram J. (1960) Notes on the cultivated Polemoniaceae. 4. Gilia. Baileya 8: 41-47.

Jäger E.J., Ebel F., Hanelt P. & Müller G. (eds.) (2008) Rothmaler Band 5. Exkursionsflora von Deutschland. Krautige Zier- und Nutzpflanzen. Springer Verlag, Berlin: 880 p.

Johnson L.A., Huish K.H. & Porter J.M. (2004) Seed surface sculpturing and its systematic significance in Gilia (Polemoniaceae) and segregate genera. Interntl. J. Plant Sci. 165: 153–172. [available online at:

Johnson L.A. & Soltis D.E. (1995) Phylogenetic inference in Saxifragaceae sensu stricto and Gilia (Polemoniaceae) using matK sequences. Ann. Missouri Bot. Gard. 82(2): 149-175. [available online at:

Milliken J. (1904) Polemoniaceae of California. Univ. Calif. Publ. Bot. 2. Univ. Calif. Press., Berkeley.

Porter J.M. (2012) Gilia. In: B.G. Baldwin (ed.), The Jepson Manual: Vascular Plants of California (ed. 2). Univ. of California Press, Berkeley: 1043–1052.

Whiteley A.C. (2000) Gilia. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 6. Cambridge University Press, Cambridge: 110.

Taxonomic name: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith