“Everything that slows us down and  forces patience, everything that sets us back  into the slow circles of nature, is a help.  Gardening is an instrument of grace.”  ~May Sarton Gardening restores me — no matter what else is going on around me. The essay below is a tribute to my Scottish-immigrant grandfather and his garden. It first appeared a few years ago in Country Gardens and was reprinted in the American and British editions of Reader’s Digest. It’s also included in my essay collection, Writing Home.    Grandpa’s Ferns   My grandfather was the proverbial Scottish curmudgeon, born and bred on a farm in the Orkney Islands. In his last…