Accepted name: Petunia ×atkinsiana
Grown as an annual herb to about 50 cm tall but available in a range of habits. Stems with sticky hairs. Leaves elliptic to lanceolate, about 5 cm long, 2 cm wide, with a stalk to about 2 cm long. Flowers solitary, to over 10 cm long and wide, mostly funnel-shaped but extremely variable in horticulture, axillary on a stalk to about 2 cm long. Fertile stamens 4, sterile stamens 1, attached below the middle of the tube.
It appears that the numerous cultivars available are the result of selections from a complex of hybrids with the major parents P. axillaris and P. integrifolia. Cultivars are available in a range of habits, and with single, double and frilled flowers in various colour forms and petal markings. About 70 cultivars had been granted PBR status to 1998. Cultivars are often sold as named seed mixes or hybrid groups that can be reliably reproduced.There are several hundred cultivars listed - too numerous to list here.
P. axillaris grows to 0.5 m tall and has nocturnally fragrant, creamy white flowers about 5 cm wide and long, while P. integrifolia, also occasionally available, has violet to rosy flowers 3-4 cm wide and long.
Source: (2002). Solanaceae. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.