ArborDay.org, 10 trees for $20

I got 12 bare root flowering trees (crabapple, redbud, dogwood, hawthorn and crepe Myrtle) from Arborday.org for a $20 donation because I thought they’d be good for my bees without fully thinking it through. I have clay soil that stays waterlogged (6-10 inches below the surface Feb.-May). I’m planning on planting my fruit trees and berry bushes on mounds. Can I plant these trees on mounds too? We have a stand of pine/hickory on the edge of our property that I can get some good topsoil from. What should I mix with it for the mounds? Our property was part an old cattle field we think. We have 4 landed acres with a couple of pine, 2 maple, 8 oak, a sweet gum or 2 and a couple of other trees all mature. Our property backs up to a 3 acre old growth pond so a lot of water drains through our property. We planted a couple of oaks straight into the ground but they ended up dying.