At the end of every winter, there are many shrubs growing along sidewalks that are dead and damaged either by salt, wind or dogs. Are there any shrubs that I can plant in these more exposed situations and expect them to survive?
Sharon Yiesla, plant knowledge specialist, The Morton Arboretum, Lisle
First, we need to note that there are some exposed areas where we just shouldn’t try to grow plants. There’s too much ice melt or salt, and dog urine is always a problem. Evergreens are also out. There’s nothing that will tolerate wind or salt. That said, there are some deciduous shrubs that can work. Hydrangea are now a huge group, Potentilla tolerates everything, and fragrant sumac (Rhus aromatica) can survive shopping center parking lots. Rose of Sharon (Hibiscus syriacus) is tough, but look for double-flowered cultivars so they don’t go to seed so fast.
Peter Moersch, owner, Stonewall Nursery, Oregon, Wisc.
I would advise looking for something on a standard. A standard is a genetically compatible rootstock which has had another plant grafted onto it. Standards are usually 24–48 inches tall and serve to “pick up” the grafted section off the ground and make it more visible. This certainly helps with snow load and keeping plants away from doggies.
Many dwarf conifers and deciduous materials are used as grafted standards. Some examples would be dwarf white pine (Pinus strobus ‘Horsford’), globular blue spruce (Picea pungens ‘St. Mary’s Broom’), and Siberian cypress (Microbiota decussata). Many dwarf Korean lilacs (Syringa spp.) and hydrangeas are also done on standards.
Scott Stringer, certified arborist, Bartlett Tree Experts, Chicago
Starting your planting project with a soil test can ensure your tree or shrub selection has the best chance of survival and can tolerate existing salt levels. Options for shrub planting with a tolerance to salt are Hydrangea, witch hazel (Hamamelis virginiana), Spiraea, serviceberry (Amelanchier canadensis), and rose of Sharon (Hibiscus syriacus). Options for trees are Japanese tree lilac (Syringa amurensis), swamp white oak (Quercus bicolor), and in wet areas, bald cypress (Taxodium distichum).
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