In June we experienced a record rainfall of 43 inches. The previous record was 41 inches and the average for this area is 22 inches in June. Here’s a graph of the erratic 2010 rainfall (red line) compared to a 16-year average (blue line).
Back in May, I noted the early blooming of Miconia rubiginosa after the heavy rains in April.
Now, in July, I’ve seen two plants in bloom that I normally see bloom in August: a tree with large bunches of yellow flowers, Senna hayesiana, and a miniature relative of the Elephant Ear herb, Xanthosoma mexicanum. I’m also seeing flower buds on an unidentified Miconia that usually blooms in September. I’m sure more’s going on along this line than I’m seeing.
Maybe these large swings in time of blooming are relatively normal for the tropics. But I’m starting to think that it’s more than coincidence that different plants from three unrelated families (Senna = Fabaceae or bean family, Xanthosoma = Araceae or arum family, Miconia = Melastomataceae or “black mouth” family) are blooming immediately after uncommonly large monthly rainfalls.
No coincidence here. Lacking other environmental cues, many tropical plants respond to rain events to coordinate their flowering. At one extreme you have the tropical wet-dry forests where everything dries out and then springs back to life when monsoon rains begin. Even in the wet tropics, many plants flower following big rains. Years ago we documented the flowering of a native nutmeg in Queensland where the trees sort of began flowering irregularly, but then after a big rain event, 100 mm or more in a week (and you’ve certainly had that by a factor of 10), and 18-21 days later all the trees reached peak flowering. Some Panamanian trees do similar things. Good observation.
Yes, we have had alot of rain here in Boquete this winter. When will we ever see the San Juan summer?
Ah, Phyto, I was hoping you might see this and speak up. Thanks. What you say makes imminent sense, but in my admittedly superficial online searches I hadn’t seen this sort of thing spelled out. Nice to have your observations.
Boquete Real Estate – Maybe today! Except by now it’s San Santiago summer, I guess. I think we missed the San Juan. Anyway, I have noticed that you had even more rain than we did in June. Some records, eh?
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