Plants good for a heavy clay soil?

You are in the same zone as I am and glads will not survive over the winter. They need to be dug up and stored over the winter like dahlias. Usually only half the mums will live over winter unless you have purchased the hardy ones. No plant likes clay..I find the best way to plant in this soil without digging it out is to dig a hole and put new rich top soil in the hole which I am planting my new plant in. Make the hole larger than the actual root of the plant so it can spread a bit..but honestly nothing loves clay soil..try any plant that will not have to root deep..iris are good for this and ornamental gres are usually good in this too as the clay does not seem to smother the roots or dwarf the growth too much.