Lavender, sedums, succulents, salvias, sage, thymes and many other Mediterranean plants prefer a lean soil that drains quickly. Don’t waste your compost or leaf mold on these low-water-use plants.

When she has used 9-inch pots, she has shaken off every bit of soil from the plants’ roots: “You have to make sure the nutrient is lean.” The point of lean soil, as her friend John Little ...