I recently noticed some odd flowers on the Pelargonium peltatum (ivy geranium) that's growing up the arbor above the gate that leads from my cutting garden to my dry garden. A handful of flowers were smaller and lighter in color than the rest. My first thought was that maybe the flower buds had been scorched by the intense sun that accompanied the extreme heatwave in July. I deadhead the shrub regularly so the unusual flowers were soon gone and I didn't think about them again until I noticed yesterday that they'd reappeared.
I know that plant viruses are responsible for much of the variegation we see in foliage and I remembered that a virus was responsible for color breaks in tulips. I conducted a cursory search and discovered that such breaks have also been observed in Pelargoniums. This is what a 1989 study by The University of Illinois Extension said:
This rare disease is caused by the Pelargonium flower break virus (PFBV). Although serologically distinct from other viruses that infect geranium, PFBV is difficult to detect because it occurs in low concentrations in the plant and is symptomless in most cultivars. Susceptible geranium cultivars show a breaking of flower color which appears as light colored streaks in the petals. Plant growth is retarded and flowers are smaller with rugosed petals. The virus has only been isolated from P. zonale and attempts to infect P. peltatum have failed. The virus is transmitted by infected cuttings, grafting, and sap.
While the 1989 study cited no evidence of PFBV in ivy geraniums, a 2012 article in a scientific journal listed Pelargonium peltatum as another host for the virus. How my plant was infected isn't clear to me. I'm going to cut back the plant as usual this fall and wait to see what happens. The references I scanned indicate there's no known treatment for this virus.
Coincidentally, I noticed that one of the dahlias in my cutting garden, 'Punkin Spice', also produced flowers in two distinctively different colors on the same plant this week. The colors of dahlia blooms can change dramatically as they mature but these two blooms opened at almost exactly the same time.
Looking into this anomaly yielded the conclusion that variations among dahlia buds on the same plant are quite common and in fact have been exploited in developing new varieties. I've no intention to get into breeding dahlias at this point, however.
This overview of floral anomalies is my Wednesday Vignette. Visit Anna at Flutter & Hum to see what images she and other contributors have found of interest to share this week.
All material © 2012-2018 by Kris Peterson for Late to the Garden Party
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| The photo on the left shows the flower's usual appearance and the one on the right shows the anomalous blooms |
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| This is a fuller view of the plant, which I brought with me in a pot when we moved here 7+ years ago. Only a few of the smaller, lighter blooms are showing at present. |
I know that plant viruses are responsible for much of the variegation we see in foliage and I remembered that a virus was responsible for color breaks in tulips. I conducted a cursory search and discovered that such breaks have also been observed in Pelargoniums. This is what a 1989 study by The University of Illinois Extension said:
This rare disease is caused by the Pelargonium flower break virus (PFBV). Although serologically distinct from other viruses that infect geranium, PFBV is difficult to detect because it occurs in low concentrations in the plant and is symptomless in most cultivars. Susceptible geranium cultivars show a breaking of flower color which appears as light colored streaks in the petals. Plant growth is retarded and flowers are smaller with rugosed petals. The virus has only been isolated from P. zonale and attempts to infect P. peltatum have failed. The virus is transmitted by infected cuttings, grafting, and sap.
While the 1989 study cited no evidence of PFBV in ivy geraniums, a 2012 article in a scientific journal listed Pelargonium peltatum as another host for the virus. How my plant was infected isn't clear to me. I'm going to cut back the plant as usual this fall and wait to see what happens. The references I scanned indicate there's no known treatment for this virus.
Coincidentally, I noticed that one of the dahlias in my cutting garden, 'Punkin Spice', also produced flowers in two distinctively different colors on the same plant this week. The colors of dahlia blooms can change dramatically as they mature but these two blooms opened at almost exactly the same time.
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| The maturity of the bloom isn't a factor in the color differences shown here |
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| This photo shows the 2 flowers on the same plant, although growing on different stems |
Looking into this anomaly yielded the conclusion that variations among dahlia buds on the same plant are quite common and in fact have been exploited in developing new varieties. I've no intention to get into breeding dahlias at this point, however.
This overview of floral anomalies is my Wednesday Vignette. Visit Anna at Flutter & Hum to see what images she and other contributors have found of interest to share this week.
All material © 2012-2018 by Kris Peterson for Late to the Garden Party