Monday, December 6, 2010

Hybridizing Petrocosmea - A Family Portrait


A Family Portraint showing P. rosettifolia #3 in the back, the seedpod parent of my first two hybrids...P. 'Keystone's Bantam, in the front, left and P. 'Rosemary Platz' on the front right.


With Petrocosmea season in full swing here in southwestern Pennsylvania, I'm enjoying an abundance of bloom. Yesterday I counted 58 Petrocosmeas in bloom, with almost as many still forming buds and yet to flower. But, no matter how many Pets I have in bloom, or how many are yet to come into my collection, two will always remain special in my heart...my first two hybrids. Petrocosmea 'Rosemary Platz' and P. 'Keystone's Bantam' are now currently in flower along with one of the parents P. rosettifolia #3. I had to take this occasion to take a photo of the three together for comparison.


P. 'Keystone's Bantam' with it's white flowers, each larger than it's leaves, and P. 'Rosemary Platz', which seemed to inherit all of the best features of both parents of the cross. I still have such a clear memory of the morning in October, 2007 when I made the cross, by applying pollen from P. sericea to the flowers of my favorite form of P. rosettifolia...the form I labeled #3. Within a couple of weeks, the seedpods were forming, and I remember thinking that they would probably contain no seeds, or if they did have seeds, they would not germinate. But, those three pods DID contain viable seeds and they were planted the following January, 2008. First flowers appeared in October and November of that same year. Through the whole process, I remained in disbelief that I had been able to finally produce seedlings after ten years of failed attempts.

Little 'Keystone's Bantam' was the oddity of the cross. It remained tiny from the very beginning. While it's siblings all grew quickly, it reached about 1.5 cm and stopped getting larger for months. Finally, that tiny green button of foliage did slowly get larger until it was 2 inches in diameter, when buds began to form. That original plant, shown above, remains under three inches today...more than three years later. This is it's third year of bloom. The tiny leaves are deep green, almost black at times, with the lighter yellow central veining of its P. rosettifolia parent. This was also the only white flowered seedling in the batch of more than thirty that I have flowered to date. The only 'tiny' one. I chose the name in honor of my dear friend and fellow Petrocosmea enthusiast, Paul Kroll. In addition to growing spectacular Petrocosmeas, as well as most other gesneriads, Paul grows, shows, and judges Japanese bantam chickens. The fantailed appearance of the flowers on 'Keystone's Bantam' reminded me of Paul's little chickens. Paul grows tiny little chickens, but his Petrocosmeas are gigantic.... I often say the Paul Kroll can grow a 12 inch Petrocosmea in a bottle cap! He phoned me this evening to tell me that his own plant of 'Keystone's Bantam' is now in bud also!!


The star of my first hybrid cross is indeed P. 'Rosemary Platz'...my very first named hybrid Petrocosmea. I named this hybrid in honor of another cherished friend - Rosemary Platz from Long Island, NY. Everytime I see this plant flower, I am reminded of how lovely my friend is. The flowers on this hybrid have a pleasant yellow throat with white and silver lavendar lobes on the corola. Flowers most resemble the P. sericea parent. Leaves are glossy, intermediate in shape and size between both parents, and with good culture, often show a subtle lighter veining. I have been very proud to see this hybrid showing up an winning some blue ribbons in shows when exhibited by other growers.