Silver Leaved plants in our Library Planters - what are they?

David Olds  has been asked what these aromatic slightly pungent soft silver feathery plants are. A friend visiting us suggests they are one of the many lovely Artemisia, probably Artemisia abrotanum  also known as southernwood, lad's love, maid's ruin, old man, boy's plant, appleringle, Our Lord's wood, garden sagebrush, slitherwood and lemon plant.
They have a strong smell and bitter taste which deter animals eating them although Lepidoptera Moths larvae like them. They are often used as an air fresheners. They are found in Eurasia, Africa and North America. Their silvery appearance is because they are covered with white hairs and this makes them drought resistant. They are easy to grow, take cuttings from and this plant gained an RHS Award of Garden Merit.