Four years ago, on a cool June day, my mother-in-law, Nancy, died after a mercifully short period of intense suffering from Alzheimer’s disease. Though she had a small garden at the family cabin years ago, Nancy was never a big gardener. But she did like having a few houseplants around. And she took great care of them, including the African violets, which just about everybody kills.

She had only one special plant, a rabbit’s-foot fern (Davallia fejeensis) that had belonged to her mother. Native to Fiji, the odd-looking fern gets its name from its long, furry rhizomes, which grow out across the soil until they hang over the edge of the pot, at first like a cute little rabbit’s foot and later like the legs of a spooky giant spider. You couldn’t help but notice this plant, and yet we realize now that it was trying to tell us that Nancy was ill long before we understood her memory was deteriorating.

Researchers are increasingly reporting the various ways plants communicate with each other. Sending messages through the soil, they warn of things like pest attacks and overcrowding. Communicating with humans is not so symbiotic. But plants tell us things as best they can. The rabbit’s-foot fern’s alert was subtle. Situated for years on a little table in front of the French doors that led out onto Nancy’s small patio, the fern was always lovingly watered and tended.

And then one afternoon I noticed that the fern’s foliage was drooping, and a lot of those little furry rabbit’s feet were drying up and shriveling. Some had even fallen off and were scattered on the normally scrupulously vacuumed white carpet. I felt the soil — bone dry. So I grabbed the watering can and gave the plant a drink, not understanding what the dire state of that family fern meant — Nancy could no longer take care of it herself.

But the slow-moving disease soon picked up speed. And in a handful of months, my feisty, beautiful mother in-law, who loved beer and Bloody Marys, NASCAR and Willie Nelson, forgot how to make the family’s favorite salad dressing, a staple atop iceberg lettuce at every dinner she served. That Christmas, when she asked what she could bring for the holiday meal, Nancy’s face went blank when we suggested blonde brownies, a treat she’d been making regularly since my husband, Mike, was a boy.

“What are blonde brownies?” she asked, before insisting that she’d never made them in her life. Desperate, we showed her the grease-stained blonde brownie recipe card she always kept in the cupboard beside the stove. Seeing it only seemed to strengthen her unwavering insistence that she was “FINE.”

There were falls and other indignities that no one should ever have to suffer, and then we had to move Nancy into a memory care unit where she could get round-the-clock care. We moved the fern with her. Perched awkwardly on top of a dresser in the small room she shared with a roommate, it was there when she no longer recognized it or anyone else except Mike, who visited her nearly every day. When she stopped talking and began refusing food and water, the nurse told us she had seen this many times before and it meant, “Nancy has decided she wants to die.” We understood. She never liked being bossed around. We stayed by her side, grateful to nurses who eased her suffering with morphine and ours with cookies and coffee.

When she was gone, the rabbit’s-foot fern came home to live with us. Having been neglected for many months, it was in bad shape, and I worried that I wouldn’t be able to save it. Four years on, though, it’s looking pretty good, with lots of new leaves and a whole bunch of those little rabbit’s feet poking out everywhere. The trick, I’ve learned, is to spritz those feet with a little water every other week or so. I think of Nancy every time I do it. The long-lived fern isn’t as lush in my hands, and I imagine it misses her. If I could, I would ask it to tell me her secrets. I’m sure it remembers them.

Meleah Maynard is a Minneapolis-based writer and editor who blogs at livinthing.com.