In article ,
says...
Jeff Layman wrote:
Emery Davis wrote:
Billit wrote:
I would like views on growing Acers in tubs, Could anyone tell me the
size of tub required and also the compost that would be most
suitable.
MO is drainage is everything, not too much peat (hard to wet once
dry) and not to acid. Acer palmatum should not be planted in
straight ericeous compost.


Yes, just about all refs give the need for "well-drained" soil.

But where did the statement about ericaceous compost come from? According
to the RHS Dictionary of Gardening, "Most species prefer a neutral to
slightly acid soil". None of the books I have make any reference to not
using straight ericaceous compost.

See for example here
http://www.bbc.co.uk/gardening/plant...ges/1579.shtml
(and other pages with a google search on "acer" and "ericaceous compost").

FWIW, I have grown A. palmatum "shindeshojo" in ericaceous compost for 7
years. It continues to do well, and IMHO is still the best red-leaved
palmatum cultivar around.


But for how long does ericaceous compost stay acidic? Whatever is added
to it (sulphur?) must wash out pretty quickly.

If peat or bark based it will tend to be acidic most composts have a bit
of lime added to make them slightly alkaline, so the problem exists the
other way ie standard potting composts after time will become less
alkaline and may become acidic. Its a slightly different story with JI
composts as it does depend on where the Loam comes from.
--
Charlie Pridham, Gardening in Cornwall
www.roselandhouse.co.uk
Holders of national collections of Clematis viticella cultivars and
Lapageria rosea