I would appreciate any advice for this newbie, and apologies if this
is a stupid question.

I recently had someone clear a patch of weeds from the corner of the
garden, and put some mulch down. I had a bit of old pond liner lying
around, and they asked if they could use that as a layer beneath the
mulch. I said yes, and they did the job. Now I'm thinking -- hang on,
pond liner is designed to be waterproof obviously, so the rain will
not drain off. I know that the stuff you buy from garden centres is
usually permeable for this reason.

Anyway, does this matter? Should I just punch a few drainage holes in
the plastic? Or am I destined to have a waterlogged patch of the
garden?

PG