One of the delights of working with plants is that one never knows what they will do..how they will perform. Just when we think we've figured out what triggers them to bloom or what they need to grow well, they fool us. I think this is my favorite trait of plants....they remain creations of nature and they remain governed by it, no matter what we as humans attempt to impose upon them.
And so it is also with Petrocosmeas and my love affair with them. Having proven and tested the hypothesis that they need cool and dry conditions to trigger bloom....my Petrocosmea parryorum has shown me clearly that I don't know anything....it is blooming for the second time in nine months and is putting up bloom at an amazingly profuse rate...at least for me.
Having grown P. parryorum for around ten years now, with no hint of bloom until three years ago, it is now blooming. The bloom is on my most mature plant..."the grandmother" of all my Pets....a plant that is at least 8 years old. We've had a hotter than normal summer here in southwestern Pennsylvania....with many days in the low 90's F. My basement has therefore also been warmer than usual. During my illness and hospitalizations back in May, the plant got quite dry, even wilted several times...once to the point that I feared I had lost it. You will note the browning on the older, larger leaves, and the "culture break" in the center leaves, which are noticeably smaller than the others. So perhaps that is what triggered this happy surprise of bloom?
Blooms on my 8 year old Petrocosmea parryorum, coming along in the heat of summer, and for the second bloom sequence in less than nine months....a happy, if not puzzling, surprise. The blooms on P. parryorum are clustered on a multi-branched pedicel...certainly one of the most "multifloral" of all Petrocosmea species..... Most produce one to five flowers per pedicel. 
The multiflowered, silvery-haired, bud-packed pedicels of P. parryorum have a tight curl to them as they emerge from underneath the large leaves. I have counted 17 pedicels in total so far in this bloom cycle. 
The "Grandmother" of my Petrocosmea collection, growing in the same five inch pan pot for many years now. I repot the plant every couple of years, removing some of the outer soil. replace it with fresh potting medium and reinsert it into the same pot. Here, you can see evidence of a "culture break" that occured last spring while I was ill. The plant wilted severely several times and with the resumption of good culture, has now produced a large, floriferous plant. 
The same plant, pictured from above...note the younger pedicels underneath the leaves, still yet to emerge. This promises to produce a long and memorable bloom cycle for me to enjoy. So this happy event proves that the more I learn, the less I know about Petrocosmea. Most species have only flowered once annually for me....which until now, I would have assumed P. parryorum to do also. P. parryorum has also only bloomed in winter for me previously...making this summer bloom cycle a bit puzzling. Was it the dry periods that triggered the bloom more than the cold? Is it related to the age of the plant in any way? Was it influenced by the size of the plant, and the mass of foliage, needed to support strong bloom??? Whatever the answer to the riddle, it now offers more questions for study..... but beyond all of that, it gives me pause to marvel and wonder, and thrill at Petrocosmea and Nature....... and isn't that really one of the reasons we garden anyway?
