p.k. writes

Flower Bobdew wrote:

Is it best [assuming the Acers don't look like they're about to keel
over and die, obviously] to keep them relatively low on water and
*only* water with rainwater from the butt when available, or isn't the
ericaceous such an issue with Acers and I would actually be better off
keeping them well watered with tap water. Thanks.

Acres don't need ericaceous compost- the would not like a very alkalne soil
but a convertional jon Innes mix will do tham fine so do not worry about
using tap water.

In which case, are they generally happy[ier] well watered. Bearing in
mind the kind of summer's we're having these days too.

I grew a collection from seedlings and whip a few years ago

Hmmmm... It appears I'm short of knowledge in my garden terminology
department. Uh, either that, or you were being particularly harsh! [Nah,
I don't talk to my plants, I whip 'em into shape! ]

and grew thwm in pots for around 10 years (root pruning every two
years)

A couple of mine are two years old now. Would it be wise to begin taking
them down this root pruning, erm, route? Why?

If so, care to share some tips and/or provide a useful link. Ta.

until they eventually got too big and unhappy (being random seedlings
not nnamed cultivars they were reversions to the taller growing form)

Mine [the potted ones] are 'named cultivars', but are all grafted. I'm
not sure if that makes any difference? [Incidentally, I do have a
Sango-kaku in the ground, and its taken beautifully in the 18 months
since it was planted. Someone else gave me a tip last year to
prune-it-to-shape at the end of August - which sounded criminal, with
Autumn approaching!!!! - but it really has rewarded me with becoming a
wonderful specimen this season. [I just pruned it again, very lightly
this time, today. ]

--
Flower Bobdew
South Facing Garden
South West: UK