THE OTHER ZONAL PELARGONIUMS – 6. CACTUS-FLOWERED PELARGONIUMS
By Wayne Handlos, Ph.D.
1.Original illustration of ‘Fire Dragon’, Gardener’s Chronicle, June 1899
2. flower of ‘Star of Persia’ 3. leaf of ‘Star of Persia’
4. flower of ‘Cook’s Red Spider’ 5. leaf of ‘Cook’s Red Spider’
In 1899 a new type of zonal pelargonium was introduced by Mr. Ed. S. Towell. This plant had flowers
in which the petals were curled under longitudinally. This gave each petal a quill-like or tube-like appearance.
At that time, dahlias were all the rage in the gardening community and one of the popular types – with tubular
petals – was called the cactus-flowered dahlia. Mr. Towell felt his Pelargonium had flowers which looked
like these dahlia flowers so he named his plant – the cactus-flowered geranium – and gave it the cultivar name
'Fire Dragon’ for its red color. He claimed this plant was a hybrid between ‘F.V. Raspail (a popular red-
flowered variety of the time) and another named ‘Lightning’ (The Garden, June 3, 1899, p. 396). Others,
later, thought the flowers reminded them of poinsettia bracts so this form of Pelargonium has also been
called the "poinsettia-flowered" Pelargonium. While the flowers resemble neither a cactus flower nor a
poinsettia, these unlikely names have stuck.
While cultural practices for cactus-flowered zonal Pelargoniums are identical to other zonals, these plants have
never gained great popularity – probably because the petals do not appear very broad due to their curled nature.
The Cannell (famous English nurserymen) catalog of 1907 apparently listed 28 cultivars; by 1993 (GATW) 21
cultivars were available commercially while a further 22 cultivars were unavailable (and presumed lost). The color
range includes white, pink, red and scarlet. Cultivars of different stature have been available from time to time and
range from microminiature, to dwarf to tall plants to trailers. The types currently extant include ‘Noel’ – double
flowered white, ‘Pink Poinsettia’, ‘Star of Persia’ – a double, purple red, ‘Cook’s Red Spider’ – a single, smaller
red. A green and white variegated leaf type – ‘Spitfire’ – is still available in some areas. A different cultivar named
‘Spitfire’ had plain green leaves and was available from the Hanford firm in England in 1975.
Tilney-Bassett (2008) has done controlled breeding experiments to elucidate the genetics of the cactus-flowered
zonals (although Charles Smith [GATW] gave results for crosses back in 1955). A cactus- flowered plant crossed
with a normal flowered plant produces cactus-flowered plants and normal flowered plants in the ratio of 1:1.
The cross breeding of cactus-flowered plants with other cactus-flowered plants gives three types of offspring in the
ratio of 1 normal : 2 cactus-flowered : 1 teratoid offspring. (These latter plants have abnormal stems and leaves
and do not flower.) Tilney-Bassett has named these alleles Cab and Caq . Plants with quilled petals have the
heterozygous genotype Cab Caq, normal flowered plants are homozygous CabCab, while the abnormal plants are
homozygous CaqCaq. He calls this situation one of semi-dominance (or incomplete dominance).
Among the California breeders of pelargoniums, Holmes Miller, Mrs. Harvey Smith (‘Noel’ and ‘Star of Persia’),
Wm. E. Schmidt who also named and released Mrs. Smith’s cultivars, and Harry and Clara May introduced
cactus-flowered cultivars. While lovely and worth growing, this type of zonal pelargonium is little-grown today
and deserves to be more widely grown.