Charlie Pridham wrote:

Boxes are fine at the nursery but at shows and plant sales, we use
bags, some customers bring their own, but we need to sell to people
that did not realise they wanted to buy something as well! so if
anyone knows of bags like plastic carriers but not made of plastic,
we remain interested to hear about them.

Try Bio bags:
http://www.biobag.no/default.pl?showPage=246

I was going to suggest compostable nappy bags but thought they might be too
small for your plants.

--
Linz
Wet Yorks