In article , Mike
wrote:


Apparently a 180 litre water butt will keep a gravity-fed dripper
system running for up to two months without rain.


I would imagine this depends on the length of hose or area. Can you give us
an idea please as we have 8 water butts and could use the system in various
places in the gardens.

Try the Hozelock Helpline -- 08708 501959. The specific claim applies
to their new water butt drip watering kit which comes with 10m of
feeder hose and 15 drippers. But if you wanted to extend a gravity fed
system you will be limited in length by the water pressure. You can
increase the pressure by raising your butts ever higher but there will
still come a point when the water can't reach the end of the hose - in
which case you should look at using a submersible pump in the butt.