Gaillardia aristata & Gaillardia pulchella.
These are the two species seen in Australia and both have numerous varieties and cultivars.
G. aristata is a perennial herb up to 70 cm high with simple hairs on the stem and leaves.
G. pulchella is a annual up to 50 cm with multicellular hairs.
Basal leaves in G. aristata have a long petiole while those of G. pulchella have a short or no petiole.
Both have hairs.
Terminal heads in G. aristata are up to 10 cm wide, those of G. pulchella are half that.
There are also differences in the involucral bracts.
Both have ray florets with yellow corollas and a red or purplish base.
Both have single and double varieties with various combinations of colours.
However most plants seen here are Gaillardia × grandiflora hort.
This is a natural hybrid of the two species.
These hybrids are compact short-lived perennials 0.4 to 1 m high and 0.5 m wide.
Basal lance-shaped leaves are up to 15 cm long and 2 cm wide.
Stem leaves are smaller and the peduncles are leafless.
Flower heads, up to 10 cm across can be single or double.
The single or bicolour ray florets are a mix of shades of yellow, orange, red, deep red and apricot.
Disc florets can be brown, burgundy, deep purple to almost black.
The genus notes have more information and illustrations of Gaillardia flowers.
J.F.
