Persephone wrote in message
Some of my veggie patch has bare dirt that dries out fast.
I don't have enough home-made compost to do much,
so wondered if anybody had experience using worm castings
as top dressing. I have quite a bit of that left over.

Wow. I'd think that using worm casting to stop drying out would be like
using gold. It'd work but seems to me to be a bit of a waste. Do you have
access to a less precious mulch that would do the same job? For around
small veggies and seedling, I use horse food ie chaff. It's very fine, and
once watered and settled in, doesn't blow away but keeps in moisture quite
well in addition to adding to the humus levels of the soil.