I may have stumbled on one of the natural world’s miraculous mysteries. Those are the categories of things that we understand happening, but can’t figure out how. For example, how is it that the fourth generation of monarch butterfly born in New Jersey can fly each fall to overwinter in the same group of evergreens in Mexico, a journey of almost three thousand miles? How does a week-old fawn know to withhold urine and feces (which might disclose its location to a predator) while its mother is away? How does a salmon, after swimming in the wide ocean for two years, find its way up a freshwater stream to the same place it was hatched—to lay its eggs and die? Why do gray whales leave the Bering Sea, navigate the west coast of Canada and the United States, and return each June to Scammon’s Cove on the Baja Peninsula to deliver their calves?
Sunlight, starlight, seasonal changes, even changes in atmospheric pressure all seem to play a role in these behaviors. At the moment, I am wondering whether plants can tell time.
A couple of years ago I discovered that that the Eastern prickly pear cactus (opuntia humifusa for gardening nerds) might grow in my northern New Jersey garden. That, I thought, would be cool. I might be the first one in the neighborhood to have a cactus in my garden. I bought four from a place in Arizona, planted them in the spring and nurtured them. No flowers, of course, but they did grow bigger.
The following spring, after a moderate winter with some snowfall, there were three cactuses (cacti?). Turns out that desperate mice burrow through the snow and will eat leathery cactus. One was a goner; the other three were nibbled upon, but thrived in spring.
Last June I noticed large new cactus ears supporting what looked suspiciously like flower buds. At the end of June, four of them opened—to disclose beautiful yellow flowers with orange centers hosting golden pistils. The ones from this year are above.
I take lots of pictures of flowers. I have a good camera (no smart phone, dammit!) that records the time and date a picture is taken in metadata. Early this month as promising growths appeared on the opuntia, I checked to see when the flowers bloomed last year. June 30.
Here’s the thing. A few days ago, on June 30, 2017, the blossoms on my cactus opened. The last two winters were wildly dissimilar. Winter before last we had thirty inches of snow in twenty-four hours and frigid weather through April. Last winter there was little snow and balmy weather in February. I don’t think the weather provided blooming signals to my cactus.
So, I’m wondering. Is this one of nature’s miraculous mysteries? Does opuntia tell time?
Check back next June 30. We’ll see.