Many recent shrub introductions have offered northern gardeners colorful foliage to accent their gardens. Whether it is the reds or purples of ninebark, the chartreuse of spirea or sumac, or a great variegated dogwood, foliage can brighten up our gardens all season long.
Until recently, we’ve not had shrubs with silver foliage. We have some great silver-leaved perennials, such as Artemisia (‘Silver Mound’ and ‘Valerie Finnis’) and Stachys (lambs ears), but not a woody shrub.
That has all changed with the recent introduction of a native sageleaf willow cultivar called Iceberg Alley™. This little gem of a shrub was discovered at the Memorial University of Newfoundland and Labrador Botanical Garden in Canada.
Hardy to USDA Zone 2, this shrub will work for all northern gardeners. The very textural foliage feels hairy and soft, and has a lovely silvery hue. As you can see in the photo, the leaf is longer than it is wide. The silver is apparent from the moment leaves emerge in spring through autumn, when they turn yellow (unfortunately not a spectacular yellow) and then eventually fall off.
Iceberg Ally sageleaf willow is relatively small, so it will fit in urban yards and foundation plantings. You could even use it as a dramatic backdrop to your perennial garden. At maturity, it’s 3 to 5 feet tall, with a spread that is slightly larger than the height. It requires little pruning, unless you want to control the height or spread. If that’s the case, prune away, as it tolerates pruning well.
In spring, it produces a pretty silver catkin with red stamens that can be cut for early spring decoration. Iceberg Alley is a male plant, which produces pollen and nectar. Researchers in Canada observed it to be a favorite of honeybees, bumblebees, syrphid flies and some butterflies.
As with most Salix, it tolerates moist soils but does not require them. It is best grown in a site that gets about six hours of direct sunlight daily. It has no major disease or pest issues. This shrub is very easy to grow. It is propagated via softwood cuttings and is protected by a plant trademark.
Pair it in the foundation planting with Hydrangea paniculate, which blooms in mid- to late summer, or with other shrubs with foliage colors that will contrast with the silver. It looks especially striking next to shrubs with red to purple foliage, such as the many ninebarks on the market.
Introduced in 2019, Iceberg Alley should be available in local garden centers this summer and fall.
Debbie Lonnee works in the horticultural industry and gardens in South St. Paul.