Sheila Richards writes

I have a largish (4 ft?) acer palmatum in a container. It seems very happy
and is growing well. However, one branch is growing in the wrong direction
and makes the plant look a very odd shape. I'd like to remove this branch
to improve the shape - can I do it at this time of year or would that be a
bad idea?

Took advice from Mr Acer at the local garden centre a couple of years
ago. One of the best times to prune is end of August [so you're still
about there - assuming you're not in a severe frosty pocket], as it
gives the plant plenty of time to recover and encourage new shoots come
spring.

The only time to really avoid pruning them is when the sap is rising,
particularly early spring, as they bleed quite heavily. However, I even
have a tip for that... Should you accidentally damage a tree [as I did
my Acer with a careless swinging spade. D'uh!] or notice bleeding from
recently pruned joints, apply some garden soil directly to the wound.
Apparently, the bacteria present in the soil will help the healing
process.

--
Flower Bobdew
South Facing Garden
South West: UK