Aside from the many fairly invasive forms of Artemisia, you don’t see a lot of trees and shrubs with silver leaves – yet there are several excellent ones that can add elegance to yard and garden. Here are several – dealing first with that controversial Artemisia family.
Most Artemisias are invasive and so while they can reach the size of a shrub or sub-shrub, one should be careful about inviting them into the garden.
- A possible exception is A. ‘Silver King’, which spreads by runner but can be somewhat contained by cutting off its inconsequential yellow flowers. ‘Silver King’ does tend to melt away in humid climates, but if happy can reach 2-3 feet wide and 3 feet high.
- A. ‘Powis Castle’ is another beautiful silvery shrub reaching 36 x 30”. It almost never flowers but while drought tolerant also is sensitive to too much humidity. Of course for those with humid summers that is one way to keep it in check should it get overly enthusiastic about its home.
- Common Artemisia vulgaris (Wormwood) is the plant from which the infamous drink absinthe was made. It can grow quite shrubby as it matures, and is not invasive like so many of its family. Hardy from zones 3-10.
- Brachyglottis is an elegant sub-shrub that makes a good mid-border plant. It is extremely adaptable, only despising shade and wet soils. It has rather ugly yellow flowers that can be cut off. Trim the shrub back to shape after flowers emerge – other than that it is pretty self-sufficient. It prefers sunny, well drained soil. Especially good are the B. Dunedin group and B. viravira. Hardy in zones 8-9.
- Phlomis fruticosa (Jerusalem Sage) is a drought tolerant, sun-loving plant with slightly furry foliage, which will thrive in a sheltered spot. It is frost tolerant and only needs to have the dead wood clipped out in spring. Hardy in zones 7-11, grown as an annual elsewhere.
- Elaeagnus macrophylla has silver leaves and spines that deter deer and other pests. It thrives in everything but chalky soil. A member of the olive family, it produces fruit – but it is inedible. It is a large shrub best suited for back of border or as a fast growing hedge, reaching from 6-9 feet high. Hardy to about 5 degrees F. (Zone 7) and up.
- Hebe ‘Broughton Silver’ is a small silvery shrub that can be used in the front of a border since it is only about 18” tall. It is evergreen and tolerates almost any garden conditions. It can also be grown in containers. It is hardy in zones 8 -10.
- Lavender is a shrubby plant with gray to silver foliage and fragrant purple or lavender flowers. It is drought tolerant and demands excellent drainage to thrive. It makes a great front of the border plant and is useful in creating a knot garden. It is hardy from zones 5-8.
- Pyrus salicifolia 'Pendula' is a weeping-willow leafed pear tree. Silvery white leaves appear after the blossoms in spring. This tree can reach 20 feet high and wide, and is hardy from zone 5 through 10. It can take full or partial sun and has brilliantly colored leaves in autumn. This is the only silver-leafed tree that is not particularly drought tolerant.
- Elaeagnus angustifolia, the Russian olive tree has narrow silvery leaves that look good in contrast with purple leafed specimens. It has thorny branches and inedible fruit, but is extremely hardy and can tolerate almost any condition. It does well as a street tree. The best silvery gray foliage is on E. ‘Quicksilver’, which can be allowed to grow as a tree or kept trimmed as a shrub. It can reach 23 feet tall if left unclipped. Hardy from zones 2-7.
- Crataegus orientalis (Hawthorn tree or Silver Thorn tree) has gray, deeply cut leaves. It can be trained as a topiary or left to attain its full height of 13-16 feet. Its relative, Crataegus tanacetifolia - the tansy-leaved thorn is slightly taller and has longer, downier foliage. It can reach about 20’. Both flower in spring and produce fruit. They are hardy from zones 6-9.