This silvery plant that does not bear flowers has long, lacy leaves and is used solely for its foliage. Use it to give nice color to the garden bed. One of the more refined artemisias, Powis Castle sage has leaves like a soft dusty miller. Hardy only to USDA Zone 6, it is well worth using in the northern part of the state as an annual. Today's plantsmen consider this the finest artemisia available to gardeners.