Author and blogger Neal Sanders introduces himself at New Salem Public Library in his humor-filled presentation on horticulture.

NEW SALEM — Neal Sanders and his wife went online to learn to how rid their gardens of slugs.

A Google search offered up millions of suggestions: lava rocks, quassia (native to Ecuador and $400 per ounce), dryer lint, quackgrass, wormwood tea. The answer, the Sanders found, was buried in the internet. Inexpensive iron phosphate.

“There’s no drama to it, so as far as Google is concerned, it doesn’t exist,” he said. “Google doesn’t know the difference between good and bad advice.”

Sanders was chock-full anecdotes like that when he spoke to a crowd of like-minded people at the New Salem Public Library on Thursday night, for a humorous horticulture presentation he calls “Gardening is Murder.”

Sanders is a mystery writer, public speaker and blogger based in Medfield. He visited New Salem to share with roughly 15 people his documented trials and tribulations of those with “green thumbs.” His wife, Betty, is a lifetime master gardener with the Massachusetts Master Gardeners Association and a nationally accredited flower show judge who has studied gardening at the Arnold Arboretum, the New York…