On Wed, 03 Jun 2009 20:51:41 +0100, Chris Hogg wrote:

Layering is a technique for propagating rhodies, camellias etc.
Basically, you take a low growing branch that can be brought down to
the ground without breaking, abrade the underside of the bark over
about an inch and then peg or weight the abraded part down onto the
ground with a stone. Leave it undisturbed for maybe a year or so, and
if you're lucky it will have rooted into the soil. It helps if that
soil is nice and peaty and moist. Gently turning up the free end so
that the branch is slightly bent at the point of abrasion is also said
to help as it slightly restricts the sap movement from the parent
plant at that point. When it's well rooted, you can cut the branch
between the parent and the rooted section, and transplant it to
wherever you want. I suppose it's a bit like strawberry runners, but
on a much longer time scale.

Ah! that ties in nicely with some advice I got from Charlie Pridham
for dealing with heathers which had become hopelessly leggy. I hadn't
realised it was called layering. Also, your useful extra detail about
abrading and gently bending - much appreciated.