Q.snowmound spirea in Michigan, zone 5
I planted 2 snowmound spireas in the late summer and they stayed green until cold weather when leaves turned brown but did not drop. Are they dead? (I’ve heard that some deciduous shrubs/trees did not drop leaves because winter came too soon – same as my Japanese Maple)
I'm in Michigan too and the combination of a decent fall and cold December seems to have thrown the bushes off kilter. Several of my bushes also have old leaves clinging to them. Since we had decent snow cover, which is great insulation for plants, I believe your spireas will be fine. I see winter die-back on my roses canes. You may have tips that don't green-up and these should be trimmed back in spring. Remember not to fertilize or prune for at least 6 weeks before first frost to encourage plants to prepare for winter. Somehow, that preparation message didn't get through last fall.