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how long the irrigation drip line maximum?

so last summer I spent too many hours every day watering the raised beds for my tomatoes at the back end of the garden (it paid off at the end, very huge delicious crop, 100+ jars). It was my first year of tomatoes. Next summer I'd like to install a drip line irrigation system.
What's the maximum I can have the drip line? 10m? 20m? 50m? 100m?
Of course it depends on the water pressure, the higher the pressure the longer the line can be. No clue what pressure I have at the tap...


  • Pete.8Pete.8 Posts: 10,313
    I use one of these to water part of my garden that gets very dry.
    I bought it in 2018 and it has performed well over the last 3 summers.
    I leave it on for 2-3 hours and job done!

    It's best laid out in warm weather when the hose is more flexible as it has a tendency to kink and curl-up if it's cold.
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • AlbeAlbe Posts: 123
    Thanks Pete.
    This is exactly the kind of stuff I'm looking at. The one of your link is 100m. I guess you also have "normal" tap pressure. Do you use the whole 100m?
    I plan to chop it and make several segments, "branches", out of it, I expect this will not impact the performance.
  • Pete.8Pete.8 Posts: 10,313
    The one I have is 50m and I use it in one single length.
    The water just dribbles out slowly and evenly the full length of the hose. I've been very pleased with it.
    If you get the same as I have, do bear in mind the bore is slightly larger than normal so you need non-standard fittings, which I managed to find in my treasure-trove of a shed.
    You can also get the same sort of hose with a standard bore.
    Tap pressure here is very good according to various plumbers over the years.
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • KT53KT53 Posts: 8,048
    The walls on a soaker/seeper hose are thicker than a normal hosepipe so you may have problems finding fittings if you cut it.  You may also find that the first section of seeper lets more water through than each subsequent section.  Multiple branches are likely to affect the flow adversely too.  Slightly different situation but I wanted to put 2 lawn sprinkers on at the same time but found that from having one sprinker which would throw an arc of water the full width of the lawn, adding a second resulted in neither throwing water more than 3 or 4 feet.
  • KT53KT53 Posts: 8,048
    Drip lines can certainly be set up easily over long distances using standard hose for parts you don't plan to have drip feeds.  Then you simply tap off with microbore wherever required.  I have a total of about 25 metres of standard hose, with microbore feeds, supplying roughly 40 pots and baskets throughout the summer.
  • AlbeAlbe Posts: 123
    Here we go physics calculation....
    Can one connect the drip irrigation system, or soaker hose, to a rain water tank?
    Water height of 1m gives pressure of 10 kPa, so 1.4 psi (a "normal" tap pressure is 40-60 psi). Drip irrigation supposedly require a minimum pressure of 10psi.

    It seems gravity system have too low pressure for the the drip irrigation or soaker hose.
    Anyone has experience to share?
  • Pete.8Pete.8 Posts: 10,313
    You are correct - the pressure will be too low.
    There was a thread last year and I think that the butt would need to be raised to approx 10ft above ground level to provide sufficient pressure
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • AlbeAlbe Posts: 123
    Thanks for the comment, Pete.
    Actually I think even 10ft is a) already too high to make it practical, after all my water would be collected by the garage roof, itself barely 10ft height, and b) still a little too low to give good pressure....
  • You can always fit an in-line water pump if you wanted to use your rainwater tank.
    Sunny Dundee
  • TopbirdTopbird Posts: 7,897
    If you end up connecting to a mains water tap, don't forget you are required to have a fitting which ensures 'dirty' water can't syphon back into the mains water system.

    I think many modern garden taps have this as part of the tap fitting, older taps don't. You can buy a fitting from Hozelock and other retailers if you're not sure.

    PS Please don't ask the cut off between 'old' and 'modern'. 
    Heaven is ... sitting in the garden with a G&T and a cat while watching the sun go down
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