In article , Janet Baraclough
wrote:

The message
from Stan The Man contains these words:

In article , Janet Baraclough
wrote:

In many parts of the country, you could water them once, at planting,
and never need to water them again. It all depends on your local
rainfall, the kind of soil you have, the lie of your land.

You would be taking a very big risk with new hedges or other shrubs if
you only gave them an initial watering.

That is not universally true throughout the UK. As I said above, in
many situations, there's no need to water at all depending on plant
type and size, temperature, time of year, a retentive soil, a sheltered
place, a high-rainfall area, or planting bare-root deciduous plants in
winter. I've been not-watering autumn/winter/spring plantings for
decades, either in my gardens and wood, other peoples' gardens, a
National Trust garden, or assorted reforesting programmes. If not
watering at planting, or ever, was high risk, few industrial landscapers
or foresters would make a living.

In the Cairngorms, maybe. But you must be describing a wild and boggy
place which is far from typical. In the great majority of cases, your
advice if taken unsuspectingly could cause havoc and loss.

The OP did not give her location. I pointed out the possibility that
watering her new hedge may not be required.

Professional gardeners keep watering thoroughly even while it's raining
since most of our showers don't deliver enough.

That is not universally true, or necessary, throughout the UK.

I'll take the point. But it is true in 95% percent of the UK.