David Hill wrote:
"..........What's a water computer doing?
Turning the water of and off...."

And I thought that was a Tap.

You could make up a system with a solenoid valve to control the flow of
water and link it to a 24 hour plug in time clock (I bought 3 timers for
around £10.00)

Yes, if you have mains electricity available and you are a competant
D-I-Y er then a mains operated solenoid valve (washing machine ones
are very cheap) and a plug in timer is *much* cheaper than those
'irrigation computers'. Do be sure that you do the electrics properly
though (correctly IP rated box for the solenoid valve etc.).

--
Chris Green )

If you have a pump, best to use a mains timer - not a water computer.
Search for "mains timer" on ebay.

If you use a rainwater barrel, better use a filter - or drippers with big
holes in - or they'll get all gunked up.

Yep I'm worried too that the barrel wont create enough pressure. I'm using
gravity to lead the water from the barrel down to the "drip system" .. but I
need some kinda device to limit the flow of water to a finetuned amount of
water per hour.

What do you mean by a filter?

Coffea ramosa wrote:


Anyone using automatic watering systems for their greenhouses? I only know
of a "hydromat" and Juliana has invented sort of a drip system, with long
tubes you put everywhere in your greenhouse.

But can't you just put a big barrel of water in your greenhouse, and rely on
evaporation-humidity to do the job?

Presumably you have ventilation in your greenhouse? The answer to your
Question should be self explanatory.

Don't bother with branded systems such as Gardena/Hozelock etc. The
retail markup is outrageous and they aren't of such great quality... get
a decent one from somewhere like NA Kays or LBS Group or LS Systems.

Even Wickes do a self watering kit for between 20 & 50 quid.

Timers/programers range from about 15 - 40 quid.. Rainbird are good.

Capillary matting is good and IIRC the Hydromat system comes with a
diagram to make a DIY self filling reservoir with a piece of guttering
and an inverted reserve container.

Be wary of your water supply. Physical dirt will clog systems, bacterial
& fungal contamination will affect your plants and possibky your
health.. THis is where the pro's and cons of storing water *in* your
greenhouse come in. Some people do it to increase humidity, others say
*never under any circumstances*
//
Jim

Coffea ramosa wrote:

: If you have a pump, best to use a mains timer - not a water computer.
: Search for "mains timer" on ebay.
:
: If you use a rainwater barrel, better use a filter - or drippers with big
: holes in - or they'll get all gunked up.

: Yep I'm worried too that the barrel wont create enough pressure. I'm using
: gravity to lead the water from the barrel down to the "drip system" .. but I
: need some kinda device to limit the flow of water to a finetuned amount of
: water per hour.

I reckon:

Regularly turning existing flow off - water computer.
Regularly turning pumps on - mains timer.

: What do you mean by a filter?

E.g.: http://www.rainharvesting.co.uk/products.asp
--
__________
|im |yler http://timtyler.org/