"VivienB" wrote in message
...
On Fri, 28 Nov 2003 10:29:57 -0000, "flashgorman"
wrote:

Hi,
Does anyone know the science behind why cuttings from young plants are
more
likely to root sucessfully? RHS exam looming large...................

TIA

Off the top of my head (my biology studies were a long time ago), I
would have thought that more of the 'grow roots' auxins were being
produced in the plant. I shall be interested to find out if that is
broadly the answer the RHS want.

Regards, VivienB
Auxins is the answer. In easy to root plants the stock plants can be cut
back hard each year to produce a rush of new growth which roots more easily
but with hard to root stuff the actual age of the stock plant comes into the
equation, and with some subjects the cuttings are taken from the previous
cuttings.
Auxins also effect the shape of the plant you get, eg the cuttings from the
top of a conifer will be more upright in habit than those from the base!
choosing where on a plant you take a cutting can make a big difference to
the resulting plants.

--
Charlie, gardening in Cornwall.
http://www.roselandhouse.co.uk
Holders of National Plant Collection of Clematis viticella (cvs)