I’ll bet that in some corner of your toolshed or garage, an old hoe is leaning against a wall. A hoe that hasn’t seen use in a long, long time, having been replaced by, perhaps, a gasoline- or electric-powered tiller, chemical weed killers, or mulches. Hoeing is not much in vogue these days, perhaps because it seems to require what Charles Dudley Warner, in his 19th century classic “My Summer in the Garden,” said every gardener should have: “an iron back with a hinge in it.” But hoeing is, believe it or not, an easy, safe way to control weeds....