Stachys byzantina is a velvet-leaved clumping perennial that can form quite an effective groundcover in a hot, dry setting. Sometimes colloquially referred to as lambs' ears, it has a basal rosette of lance-shaped silvery leaves. In late spring it sends up chunky 45 cm spikes with pink to purple flowers. It is a member of the Lamiaceae family of plants and comes from an area ranging from Turkey to Iran. It needs very well drained soil and plenty of sun. It associates well with Mediterranean plantings of lavender, rosemary and tall bearded irises. It is fairly frost hardy. Sometimes it will partly rot off in our humid months of January and February in Sydney, but usually some of the plant will remain. It is beneficial to divide the plant regularly to avoid a build-up of too much foliage, as this can exacerbate the problem. There is a non-flowering cultivar called 'Silver Carpet', and 'Big Ears' has larger, slightly greener leaves than the species; there is also a pretty chartreuse cultivar called 'Primrose Heron', but I never had any luck with it.
This plant looks very effective paired with the flowers of white bearded Iris or any other white flower for that matter. It also looks fantastic grown nearby silver-leaved plants with much finer-textured foliage: in cool climates Cerastium tomentosum is a good candidate (pictured at left); in Sydney, try Artemisia 'Powys Castle' or Dichondra argentea 'Silver Falls' with lambs' ears instead. I also like growing it near dark-foliaged groundcovers such as Ajuga 'Black Scallop', for a strong contrast.
Stachys byzantina is regarded as a good bee plant.