Bill H wrote:
Hello

I have some clay pots that I have brought back from Africa, they
are
clay that has been fired in a kiln but not glazed.
The clay after firing is a terrcotta colour.

I need to protect them from the UK elements, rain and frost, no
room
indoors!

Someone suggested painting them with PVA glue which I have done,
when
sunny they have a shine however everytime it rains they turn
white!!

Any ideas

I wouldn't have recommended PVA glue, for the reasons you have
discovered. Better is an inside-and-out coating of masonry
water-repellent. But that won't protect against expansion of the
contents in a bad freeze-up: this could also crack the pots, but I
don't think it happens very often. The shape of the pot would matter,
I think: conventional conical ones are probably safer than ones which
are narrower at the top than in the middle -- we had a wooden
water-butt break when it froze solid.

--
Mike.