Planning discreet, automatic garden irrigation - underground?

Hello everyone,

or better said: Hello , since this is probably mainly a topic for you.
You already gave me valuable tips almost two years ago during the planning phase of my construction project (see ),
and now the time has actually come to plant the garden and finalize the irrigation system.

Current status: Our landscape gardener created an irrigation plan for the property via DVS, see attached pictures (orientation bottom south, top north).

In the southern area (front garden) three beds are planned between the paved areas, each with larger shrubs (lilac, viburnum, etc.) plus perennials/grasses/ground covers,
as well as two spherical maples.

In the northern area (actual garden) there is an 80m² lawn area with five spherical robinias in the middle.
Otherwise, except for the terrace areas, almost everything is densely planted with shrubs, mixed perennials, and ground covers, only stepping stones lead through the ground covers.
At the property boundaries there are evergreen hedge plants as well as a bunch of other trees (willows, chestnuts, apple, cherry, etc., >= 25cm trunk circumference) planned;
the trees are underplanted (shrubs, perennials), so everything is relatively lush.

As you can see, root zone irrigation ("P & R tree") has been planned for most of the trees; everything else will probably be supplied with drip tubing (XFS, 2.3l/h).
I don’t know exactly how many zones are planned, probably about 5 in the north, 3 in the south. There will be one valve box each for north/south plus one with the main valve and filter. Control via Pro-HC.

Now the actual problem: The missus wants the irrigation to be as inconspicuous as possible, better yet "invisible" (natural look).
In particular, the 12cm plastic caps of the root zone irrigation on the lawn area look ugly, also the exposed drip tubes are disturbing.
It might be that these are no longer visible with heavier growth, but I can hardly judge that currently.
Also, the rotors spraying the trunks of the trees on the lawn might not be optimal?

My consideration now is to switch everything completely to underground / subsurface drip tubing. But I have the following questions / concerns:

[*]Is underground installation a maintenance nightmare? You don’t notice if something goes wrong and have to dig up the garden to find leaks and blockages. Roots can grow in anytime?
[*]Presumably (per circuit??) an air release valve is required; these boxes also need to be hidden somewhere. Same for a flush valve?
[*]Drip tubing for trees is probably not optimal but better than surface irrigation?
[*]Do trees need their own circuit, or do you simply loop several radii of the tubing around the trees to get a reasonable irrigation ratio between shrubs/trees? The installation documents for the XFS tubing mainly concern lawn and beds..
[*]Cost factor: digging trenches will definitely not be cheap

Alternatively, I have also looked at so-called "micro-sprayers", where the supply lines could possibly be laid a few centimeters underground, the spray heads are relatively inconspicuous. But this is not a solution for the trees on the lawn, and otherwise I find hardly any information on planning such a system.

Has anyone gained experience with underground drip tubing and can recommend the approach? Or otherwise talk me out of the whole thing before it’s too late? ;) Alternative suggestions are always welcome.

P.S. The gardener planned everything with 24mm BluLock pipes/connectors, what do you think of this system?
I originally wanted to run DN32 in the circuits, the lines to the valve boxes are in DN40 (after complaint and replacement).
If 24/25mm PE pipe is enough for our purpose and laying it is possibly easier, I don’t want to make a big deal out of it...

Thanks a thousand in advance and regards,
Hausbaufaehig

The drip pipes and covers are no longer visible after one year. Otherwise, cover with bark mulch. The underground irrigation would be much more expensive, you cannot control it and cannot easily change anything in the garden. I had thought about it too. Whether a 24mm pipe in a loop is sufficient depends on the pipe length in the loop, the consumers, and the pump. Ask your landscaper how many m3 the individual loops require per hour and what data the pump has. The 40mm supply line to the boxes is great. Overall, it looks like a good plan. Trees also get wet when it rains. If the rotators spray for a few minutes, nothing happens. Just convince your wife that she needs a little patience and then the irrigation will no longer be visible…

Thank you very much for the extremely quick response! I had feared that the underground irrigation wouldn’t perform well :( The additional costs would also worry me; we are currently already in the almost five-figure range (half material costs, half installation). I’m trying to promote the drip tube + root zone irrigation; if you can still clearly see the drip tubes after a year, something has definitely gone wrong, the perennials/ground covers/grasses should actually overgrow everything (=> suppress weeds).

Another challenge for us: mulch is not desired, but maybe at least parts of the drip tubes can be covered with a loose layer of soil without immediately needing a balancing valve.

On the lawn area, I would simply work exclusively with the rotators; the robinias need (at least as they age) rather less water.

Regarding the division of the zones, I will ask again; based on your recommendation, I have requested a submersible pump with 6 bar / 6000 l/h, let’s see what is available here.

If anyone has an opinion on the alternative bubbler nozzle or micro-sprayer: bring it on ;)

Best regards, Hausbaufaehig

The xfs can also be covered with soil. An alternative to mulch would be volcanic gravel.