Mary Stella, a Michigan Basement is one step up from a crawl space. The original part of my son's house is so old the city doesn't even know when it was built. His furnace is down there, but I don't think there are any vents .
I have always thought Dahlias were worth growing as annuals ... I laughed when I read "allows me to feel okay about ordering some new ones."
That bed has been evolving over many years, it was once a fenced in veggie garden, to keep the dog out as much as the deer. Even had a Turkey coop in there once, so it should be fertile.
