Porous / Leaky / Drip Pipe
I'm intending to put some (at least semi-)permanent irrigation into my
fern beds. I wondered whether anyone had any views and/or experience of
the various options, sizes and makes. Any thoughts gratefully received.
- Hello Anthony, in response to your query, I installed a porous pipe
around a york stone "rockery" and along the top of a 15"-high bank
faced with limestone rocks. I still have the instruction sheet, which
carries no brand name or even an address.
The pipe can be laid in a straight line, snaking or up-and-down.
Plastic push-on connectors were supplied for joints, 90 deg. corners
and tee junctions.
The pipe can be laid on the surface or buried 4" to 5" down. I chose
to bury it, which in practice was not easy without demolishing my
rockery in the process. Consequently, there are sections of the pipe
showing, which are most unsightly and although I cover these with bark
chippings every spring, they eventually become revealed again.
Water sweats out of the pipe, although with age mine sprays finely in
two or three places (yes, I'm still talking about porous pipe!) and you
need to run it on a low tap pressure.
Water is claimed to spread approx. 1/2 metre either side of the pipe,
although this depends on the soil. What I can tell you it does NOT do
is spread upwards much, something to bear in mind when you bury it. You
also have to remember where it is, as I inadvertently cut mine with a
One disadvantage of the system is that the pipe can become blocked,
which is not easy to spot if it is buried. I suspect that the
shorter "branch" that runs behind my limestone bank does not work as
efficiently as that on the rockery.
My system is run from an outside tap by a length of garden hose. To my
surprise, both this hose and a longer one that supplies top-up valves
on my ponds have gradually shrunk to the point where I have had to add
extra lengths to them.
I use a Hozelok battery-operated electronic timer which cost about £42,
I set it to run from 12:30 am to 3:30 am, which seems to be sufficient.
Like all Hozelok fittings, the connectors drip incessantly. Disconnect
it and bring it in when it is not in use in the winter months or it
might freeze and split, as my first one did.
The major disanvantage with irrigation is that is you have hard tap
water, you will soon kill off any acid-lovers such as Blechnum, while
others that like it on the acid side of neutral will not be at their