Silver Mound Artemisia blight
My Silver Mound Artemisia was flourishing, but now the leaves around the outer edges are dying, although some new growth is evident even in the dying sections. What is happening? Could grubs cause such a condition? Should I remove the dead and dying areas? Obviously, I'm no gardener, but I do really love this plant.
While disease or insects could be at work, it's more likely that your plant just needs to be divided. Read more: https://www.gardeningknowhow.com/ornamental/foliage/artemisia/silver-mound-care.htm
You might be interested in knowing about the Agricultural Extension Service, which is paid for by your taxes, and exists in almost all counties in the USA. They have wonderful resources for helping and educating home gardeners. You can locate the nearest one with this link: