My mother-in-law has long been one of my most prominent influences as a gardener. When I close my eyes I can picture perfectly the wild English gardens surrounding her house in Durham County … the floxglove, periwinkle, coneflower, Egyptian verbena, Shasta daisies, peonies, roses, geraniums … oh, the list goes on. But “Grandpat,” as her grandchildren call her, is also an ace indoor gardener.

Whereas I’m the certain death knoll for orchids, they thrive eagerly for her. Christmas cacti are the same. The one Christmas cactus I have limps along, with barely enough life coursing through its system to stay green, let alone to bloom. But Pat’s plant is enormous, and oddly enough, blooming as we read.

Pat’s heirloom cactus, at 30, is almost as old as me. “My mother had two Christmas cacti that looked almost identical,” Pat said. “After she died, in 1984, my dad took care of them until he died in 1994, and then they came to live with me.”

Through the years, family and friends across the US have been recipients of clippings … but you can guess that our clipping didn’t fare so well. It makes me wonder what I’m doing wrong, you know. So I asked: What’s the secret to a healthy Christmas cactus—even one that blooms beyond the holidays?

“In the summer when the cactus is outside, I usually have impatiens growing nearby, and every year some of them seed themselves in the cactus plant. So when I bring it indoors for the winter, I have flowering impatiens brightening the room until they become too tall later in the winter when I pull them out.”

“During the winter, I keep it either in the dining room in a bay window, which faces southwest and gets good indirect sunlight, or in the sunroom where it gets lots of light. For the past several years, it has wintered in the dining room. After danger of frost has passed, I put it outside on the deck in a partially shady area, where I leave it as late in the fall as I can. It seems to bloom better if it has some chilly nights before bringing it inside. My parents always put the plants outside under a big water oak tree with plenty of shade in the summer. In the winter, the plants were brought inside to a sunroom that was heated a bit, but not as warm as in the house.”

“I don't overwater it in the winter—probably about once every five to seven days. I like to let it get a bit dry between watering,” she said. “I use a slow release fertilizer and follow the directions on the package. I don’t trim it, either, and it’s so big that sometimes a part will get knocked off when I'm moving it from one place to another. It’s pretty heavy and weighs about 35 pounds, so sometimes I use a cart to move it. I’ve repotted it a couple of times, but I don't like to disturb it too much.”

Well, it’s unusual for me to be the antithesis of success with any plant, so I chalk up my failure with Pat’s Christmas cactus clipping to the fact that the spirits of her parents live through it, and are happy to maintain the connection. For now, I think, we’ll just visit it at Grandpat’s.