Bushes getting yellowed edges, mottling and some dark spots

Asked July 19, 2018, 7:49 AM EDT

I planted astilbe, black cohosh and spice bush this spring in three different areas of the yard. They did well for about a month then they staring getting yellowed edges, mottling and some dark spots.

Hennepin County Minnesota

1 Response

I'm not seeing much damage in your photos. Usually, when multiple species are affected and no obvious pest is detected, we suspect something environmental. Some possibilities: nutrient deficiency (rain tends to wash away nitrogen fertilizer), soil compaction (any construction nearby?), herbicide drift (any herbicide used recently?), misapplied fertilizer and adverse weather. Here are a couple of good websites: