In article , jmsmith2011
@hotmail.co.uk says...

On Tue, 01 Jul 2014 20:20:14 +0100 (BST), "Dave Liquorice"
wrote:

On Tue, 01 Jul 2014 19:58:06 +0100, Judith in England wrote:

The grass at the side of the beds has become very, very wet - and
really never dries out: it is particularly noticeable in the morning
after the night watering session. The raised beds drain very, very
well.

I think i'd turn down the watering and keep an eye on the plants in
the raised beds.

We have the watering coming on twice during the night - for 15 mins each time -
six hours apart.
I did this last year - and the raised beds did not get "soggy" at all.

That change is significant. Two 15 min periods are hardly enough to
saturate raised beds to the point of running off. I'd suggest your timer
may have gone faulty.



All the
produce from them was fantastic. So I don't think the watering is the problem
- it is the getting rid of that water once it has left the raised beds.

That amount of water shouldn't have left the beds.



Is aggregate the correct thing to fill the trench with - or do I use
course gravel - or something else?

Take a look at http://www.pavingexpert.com/drain03.htm and possibly
other parts of that site.

Good site: thanks

We have a large soakaway we constructed 12 years ago following the
instructions of the pavingexpert, it's collecting and dispersing all
the land drainage water we installed on a half acre garden (high
rainfall here). It's still working perfectly, no soggy areas.

Janet.