need to remove soil?
I have two flower beds that I'm not sure if I should replace the soil. 1: last year's bee balm (monarda) had powdery mildew all over, and the plant is dead in the middle and only a few shoots coming up around the edge of the former plant. Want to plant a different plant. 2: I removed the stump from an arborvitae. There is an inch of dead arborvitae leaves and abundant bird seed shells. The arborvitae was overgrown and in front of the gas meter. There is another arborvitae nearby. I want to plant perennial flowers. If I need to replace the soil, where do I take the old soil?
Ramsey County Minnesota
Nothing you've told me would suggest you need to replace the soil. Monarda gets powdery mildew - it is the nature of the plant. You already suggested a course of action: replace it with something less prone to disease. Bird seed shells and arborvitae debris will actually help your soil eventually as they decompose.
If you want to improve your soil in both locations, I'd suggest working two or three inches of organic matter (compost or rotted manure) before you plant:
I'd also suggest you get a soil test so you know what fertilizer you need to apply and what your soil's pH is:
As for what to plant, you have many choices, depending on the conditions of the site (sun, exposure). Check this site: