Phil L writes
I've got some seeds started off and want to know how to retain moisture? - I
do have a few of those propogator lids (clear perspex, about 6 inches tall)
and they work fine, but I want something to cover the rest....I've tried
clingfilm etc but once the seedlings are an inch tall they hit the top, the
seed trays are on window sills near radiators and tend to dry out very
quickly.

Is there any way I can avoid spending any money?

Stand the pot or tray in a large plastic bag and tie it at the top. That
usually gives it enough rigidity to stand up in a tent shape. If not,
you can use a stick to prop it up. It's best to use several smaller pots
and trays - easier to get the plastic bags, easier to get them to stand
up.

And of course look out for clear plastic packaging - it's best to have
one lid per tray, but if you're stuck, then a mosaic of smaller lids is
better than nothing.
--
Kay