'Quicksilver' Hebe
This unique looking New Zealand hebe has dark, nearly black, wiry limbs with very tiny silvery blue-grey leaves. The limbs have a very open airy habit. It is a foot to a foot & a half tall, with a potential spread approaching three feet. It is a semi-creeper & if positioned just right will cascade off a rocky ledge.
Its small early summer flowers are a pale lilac. Appealing as the flowers are, it is the evergreen foliage that gives it year-round color & appeal. 'Quicksilver' is even used by flower arrangers because the slender black stems of silvery blue-grey leaves make such a remarkable impact.
'Quicksilver' arose spontaneously in 1965 from among regular Hebe pimeleloides seedlings at County Park Nursery in Essex. Nurseryman Graham Hutchins, author of Hebes Here & There (1997), immediately recognized its special merits & preserved it for cultivation. It subsequently received the Award of Garden Merit.
As a generality, hebes with the smallest leaves are the hardiest, & those with very broad leaves are more prone to freezing to death or rotting in winter. By this rule of thumb, 'Quicksilver' with its eency leaves ought to be very easy to grow. Alas it is one of the exceptions to the rule, & can be prone to freezing to death or rotting even in mild Zone 8 winters.
It can adapt, however, if given a sheltered location near the house under eaves, or a very sunny fast-draining rockery ledge, or similar spots where it won't remain too wet during the hard rains of autumn & winter. It can tolerate brief winter chills even into the teens, but it cannot take much wetness in months when it is dormant, though too droughty a condition should also be avoided.