Salad burnet is a low, mounding culinary herb native to Europe, North Africa, and western Asia, grown almost entirely for its ferny, blue-green foliage rather than its inconspicuous, tight round flower heads. The finely toothed, pinnate leaves carry a clean, cucumber-like flavor and stay tender and harvestable well into the cold season, making it one of the few fresh herbs still worth cutting after a hard frost has taken out the rest of the garden.
It's virtually pest- and disease-free and happy in poor, dry soil where richer herbs struggle. Regularly snipping the older outer leaves — both for the kitchen and to keep the plant tidy — pushes fresh, better-tasting new growth from the center. Left unharvested it can self-seed; shearing off the flower heads before they set seed keeps a planting from spreading beyond where it's wanted.