Hazel wrote:

writes

My soil is compacted clay, with hardly any worms.

Spread a 6 inch deep layer of compost over your borders. Worm activity
will incorporate the compost into the soil (they're fast breeders, and
even though you don't have many to start with, you soon will once you
start spreading compost).

Meanwhile start a compost heap if you don't already have one, and
continue spreading 6 inch of compost each year.

This will be more effective than trying to improve the soil by a once-
off digging in of compost and sharp sand.

I have a question for those that say to surface spread the compost. How do
you keep it in place, the birds here spread it all over the place ?

You don't. You have to put it back on the soil from time to time. The
birds are after all the worms that the new material encourages.

Same happens with bark chippings on the borders too. Nothing that a
grass rake or rough broom won't quickly sort out though.

Regards,
Martin Brown