You could dig out the area you want the plants specifically and amend the soil. Add some sort of soil condition (ie pine bark fines) and turface. I use OilDri from sams club. I just repotted a plant from 2 years ago and the stuff still hasn't broken down. It is cheaper than Turface (only $4 for 40#). If you buy by the truck load though you may be able to get other stuff cheaper. Pea gravel and soil conditioner; maybe add grit or #00 builder's sand. You could do a combination of all of the above. Square footage will determine a lot of what you do. If the clay dries out it is hard as heck. I am in Houston and all we sit on is clay. You can't even dig an inch and a half down. Good luck and post before and after pics.

Think out what you will be growing together, and remember where they grow naturally, what they grow in, and how large they will end up, get some hints from Palm Bob's pictures, he has done a great job, Norma

Thanks.. I am afraid I will have to do some ammending because of our rocky clay soil, but I have to bring in some new dirt anyway, since we just leveled off the yard.
Our soil is typ heavy clay with lots of rocks, although over the last 15 years I have been working organic matter into existing and new garden beds. Thanks Norma and Tanya... good advice!
Not sure who Palm Bob is...assuming he is posting on this site somewhere??? Will try and find his pics.