Allen Lacy, an accidental gardening columnist whose cramped backyard inspired practical advice on down-to-earth subjects like expunging crab grass and erudite cerebrations about far-flung fields like global warming, died last Sunday at his home in Linwood, N.J. He was 80.

The cause was complications of heart and kidney disease, his son Michael said.

Mr. Lacy, a philosophy professor who sowed his cultivated wit and wisdom for The New York Times and The Wall Street Journal and wrote or edited 10 books on gardening, began his love affair with horticulture in 1943 when he bit his third-grade teacher, a Mrs. Leghorn, on the ankle and was expelled from elementary school.

“I was in what amounted to a parole, supervised by a wonderful fourth-grade teacher, Ruth Harkey, who ran a small nursery and was a breeder of bearded iris,” he recalled in 2013 in an email exchange with the blog gardeninacity.

“Mrs. Harkey taught me the elements of hybridization,” he continued, “and I was hooked at the idea of interfering with nature to bring something new into being.”