String of Pearls

Senecio rowleyanus, String of Pearls, is a trailing succulent from the drylands of southwestern Africa whose threadlike stems are strung with spherical pea-like leaves, each with a translucent window down one side that lets light into the interior.
It is used in hanging baskets, planter and wall cascades and interior schemes, wherever a fine trailing line is wanted at eye level or above.
String of Pearls is a detail plant rather than a landscape one, and it earns its place spilling out of a planter at height.