Gardening Success With Difficult Soils by Scott Ogden addresses this very question. Plants of all types for alkaline soils in sun, part sun or shade. You might find it in your library or a used copy at amazon.com or half.com

Here I thought I was going to help you out.

Then, I saw the date of your posting. Undoubtedly, since it's been 6 years, you've found what you were looking for.

I'm on alkaline soil, but no shade.

Xtal

Here is a link that might be useful: Plants, Flowers and Trees that will Grow in Alkaline Soil

I think people do read these back posts. One plant that is really classy and does well in these trying conditions is hardy cyclamen. C. neapolitanum or coum. It takes a while to get established and propagate ( well it doesn't get a lot of help).

Ian,
I went to your site. OMG, I've never seen some of those orchids before. Drop dead gorgeous. You've got a good handle on growing them. I suspect your yard looks better than you lead us to believe.

Xtal