I was hoping for some advice on whether I can add topsoil at all...the earth is poor and tightly packed there
and there is a bare spot of 6 x4 that I want to put something groundcoverish on.
I never built a bed and have no gardening experience so I am starting from scratch in zone 8a.
Recommendations on part sun/under magnolia and how would be very helpful!
I can't comment specifically on magnolias, but most trees don't like to have too much soil put on top of their roots. So you might be able to add a teensy amount of topsoil, but I definitely wouldn't think about putting in a raised bed or anything along those lines.
if you are just looking to plant a GC, I dont see the harm in 3" of topsoil for their roots to take hold in. I am assuming the roots arent exposed at all? some trees have surface roots [i think beech comes to mind] and those i would try not to cover up... but if it generally does not have roots showing, there is no way 3" can hurt. if anything it will benefit the tree with moisture retention.