Opinion | What Climate Change Does to my October Garden - The New York Times

Opinion | What Climate Change Does to my October Garden - The New York Times

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Guest Essay

My Kind of October Surprise

Ms. Renkl is a contributing Opinion writer who covers flora, fauna, politics and culture in the American South.

In Middle Tennessee, October is supposed to mean golden light and falling leaves and clear nights cool enough to make you spread a blanket across the foot of the bed in case the chill turns to genuine cold. October doesn’t normally bring an explosion of butterflies. The time for butterflies is September, with its mild warmth and blooming roadside flowers — snakeroot, asters, ironweed and the splendid goldenrod — all in their fullest glory.

Weather can change from one year to the next, and insect populations vary, too, partly in response to the inconstant weather. A springtime freeze can wipe out all manner of insects just gearing up for a summer of song. Summertime drought can do the same. So can the remnants of fall hurricanes barreling north. Add habitat destruction and widespread insecticide use to the existential threats facing insects, and it’s no wonder that populations are plummeting, no wonder that every year I see fewer butterflies than I saw the year before.

This year, September brought only the barest handful of butterflies, but it has been a magnificent year for many, many kinds of bees. Bumblebees and carpenter bees, the most reliable pollinators in my pollinator garden, but also a surprising number of honeybees, tiny green sweat bees and several of the pollen-specialist bees that evolved to feed on only one kind of plant. It is always a great thrill when I discover a new specialist bee in this yard. They are here only because the right flower is here, too.

Why so many bees and yet so few butterflies? Even the gulf fritillaries, which typically arrive early, were so late this summer that I began to wonder if there would be any takers on the wild passion vines growing along the fence beside our driveway. The passionflowers were frequented by dozens and dozens of carpenter bees, the only insect large enough to pollinate a passionflower. But I added this plant to my garden mainly for the gulf fritillaries, whose caterpillars can eat only passion vine. Where were the butterflies?

They came, eventually. First just one and a few days later another, and then another. Soon they were laying eggs so enthusiastically that their caterpillars were eating the plants into lace.

Butterflies are prolific because very few caterpillars survive. In my garden, the red wasps harvested many gulf fritillary young to feed to their own young, and the Carolina wrens did the same. A few caterpillars reached a grand size — grand enough to give me hope that some of them may have crawled away to pupate in safety. Maybe some of the gulf fritillaries I’m seeing today began their lives on this very passion vine during the unnatural heat of September.

It’s impossible not to wonder if that heat had anything to do with the butterflies missing from my pollinator garden. This summer was the hottest on record, and September followed suit. That’s no surprise; every month now is the hottest on record. But September not only broke the records — it broke them by a country mile. The heat was so far beyond the norm that the climate scientist Zeke Hausfather called it “ absolutely gobsmackingly bananas.” And it persisted into the first week of October.

I know that insect reproduction is affected by temperature, and I know that some butterflies and native bees are especially affected by heat stress. I know these things because the stressors affecting wildlife are often nakedly visible to anyone who is paying the least bit of attention.

Here is a measure of my worry: When a monarch caterpillar hitched a ride home with me on a pot of butterfly weed that I bought at Wonder Gift & Garden, a desperately needed new native-plant nursery in Kingston Springs, I put it, pot and all, in a mesh cage to protect it from the wasps.

There’s no way for me to know why my garden was so bereft of butterflies all summer, and even for most of September, and yet entered October aflutter. I’m just glad the butterflies came back. On sunny days now I find big, showy monarchs and tiger swallowtails and black swallowtails and even, once, a gorgeous pipevine swallowtail. (Note to self: Plant pipevine next year.) Also clouded sulphurs and tiny sachems and fiery skippers and the little brown moths that Carolina wrens favor even more than gulf fritillary caterpillars.

But this is an uneasy joy, as pleasure in the natural world must always be these days, for the seasons have gone completely haywire. By the time the butterflies finally arrived here, the fall wildflowers were mostly gone. In my yard, ironweed came and went, snakeroot came and went, Carolina elephants-foot and blue mistflower and sicklepods, too, are now all bloomed out.

The asters are just coming into their own, though, and the goldenrod is still exploding in plumes of yellow extravagance, though they won’t last indefinitely. I generally let my zinnias go to seed to feed the birds, but this year I’ve taken to deadheading the spent flowers, forcing the plants to make new blooms for the butterflies. I’ve made a vow to plant more zinnias next year.

The monarch caterpillar I brought home emerged safely from her chrysalis — a perfect female. After her wings were dry, I carried the butterfly cage out to the pollinator garden and unzipped it. She flew straight to a stand of New England asters, a wonderful native plant that will keep making new flowers until the first frost. As with all my perennials, I will leave the blasted plants standing all winter, for their seeds will feed the birds, and their hollow stems will make a safe place for overwintering insects to take shelter from the cold.

The asters are one of the reasons I don’t worry about my backyard birds this year. The beautyberries are thick in their purple splendor and the maple trees are so heavy with seeds that smaller branches keep crashing to the ground from their weight. The Joe Pye weed has gone to seed, and so have the milkweed and the coneflowers and the black-eyed Susans. Our old oak is in the midst of a glorious mast year, and every mammal in the yard is getting fat on acorns. The squirrels carefully choose the ones they like best and leave the others for everybody else.

And thanks to all the carpenter bees, there is such a glut of native passionfruit this year that for once the critters have left enough behind for me. In all my years of growing passion vine, I have never kept even one passionfruit for myself until this bounteous year. Its sweetness is tinged with citrus, its taste an echo of tropical warmth, a reminder of a summer that tried so hard not to end.

Margaret Renkl, a contributing Opinion writer, is the author of the books “ Graceland, at Last,” “ Late Migrations” and the forthcoming “ The Comfort of Crows: A Backyard Year.”

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