In article , Chris Hogg
writes
On Sun, 2 Jun 2019 18:52:02 +0100, "Jim GM4DHJ ..."
wrote:

should they be neatly filled or does it not matter? ....

In general I thing gabions are unattractive. But they're functional.
If I was in the position of filling gabions, I'd include quite a lot
of soil along with the stone, and into the sides I'd plant perennials
that like that situation, i.e. that like growing in walls, like good
drainage and tolerate dry conditions, to mask the stones and wire.

Soil would wash out.
--
bert