David Yeardley came over today with his Ditch Witch, a trench digger, to dig the trenches
for the garden irrigation system. That went well, despite a number of strange things we found
in the ground, including pipes, mounting brackets, bolts and a horse shoe. It's amazing that
this land has only been settled for about 150 years, and already there's so much human débris
in the ground.
Finally finished my planning for the irrigation system, not helped much by the discovery
that the spec sheets I had for the microsprays didn't match the description in the planning
guide (the one I couldn't find in the Philmac technical
library, but which showed up under the obvious heading of Single Piece and
2-Piece Jets and Sprays, a page that first displays the list properly, then shrinks it to
the upper half of the page, puts in a scroll bar which uses incredible CPU resources, so much
that scrolling takes several seconds. It doesn't link to any spec sheet for the single piece
jets I was planning to use.
Then decided to print out a list of distributors for Philmac products. I had already
noticed that Midland Irrigation wasn't on
the list for Ballarat, so looked again. This time I put in my post code, though it's clear
that there are no distributors out in the sticks. Who cropped up? All the people I know on La
Trobe St, Ballarat, including Midland Irrigation. But if I entered “Ballarat”,
they didn't show up. This appears to be a problem in the search engine which relates to
specific post codes, and Ballarat has a different one. What a crock!
When I got to Midland Irrigation I discovered that this didn't really matter: they had
different, correct spec sheets (some of which even included mm rainfall/hour columns) and the
components to match them. I'm more and more amazed that a new web site can so completely miss
Finally got most things I was looking for, with the exception of low density
poly(propylene) pipe and pipe saddles (not in stock), some solenoids (too expensive at
Midland). Off to the Ballarat Pump Shop, where they didn't really have too much, and on to
Celsius (or is that Indoor and Outdoor Trends? Or just Outdoor Trends? They use all three
names, but it's the last that shows up on the invoice). There they were in the process of
changing the sales software, and it took a little longer. They had the 19mm LD poly pipe in
stock, at about $137 for 200 metres. By contrast, the price at Midland Irrigation would have
been about $65, and even the rural grade 25mm poly pipe at Ballarat Pumps cost only $109. I
can only imagine some database problem. They finally sold it to me for $70. Also picked up
the remaining components.
Then off to Middendorp Electrical, where I spent nearly $500 on very few items, nearly all
on 60 metres of power cable and 52 metres of conduit.
Spent most of the day today in the trenches in the garden. First we had to lay power
cables, which proved to be very difficult for one person and very easy for two. Somehow it
seemed to take up most of the day.
In the process, found one of the biggest ants I've ever seen. It measured 3 cm end to
Put it in the fridge to slow it down, but it was still fast enough to be difficult to
photograph. Put it in the freezer for what I thought was only a couple of minutes, but
unfortunately it was too much, and it literally curled up and died. I was rather unhappy
More work in the garden today. Finally got all the pipes connected up, so now I can at
least get water at various points round the garden. Next step is to connect up the solenoids
and decide how to lay out the sprinklers.
There are two issues here:
Controlling the solenoids. Three years ago I started
a project for a sprinkler controller based on an old laptop and a relay board. That had
ultimately died because I had burnt out the solenoids (put DC instead of AC through them),
but the equipment itself was still functional—and nowhere to be found. Before I go
crazy trying to find it, I think I'll buy a controller on eBay.
How many emitters should I put on each (pipe) circuit? That's actually quite a
complicated consideration. Ideally the pump should run all the time, which means that the
number of emitters should be matched to the flow rate of the pump at the desired pressure
(which seems to be in the 150 kPa range). And how do I find that out? And what if I change
a pump? I suppose the best way is to decide on a flow rate and just keep adding emitters
until the pressure is maintained. And if I change a pump, I may have to add or remove
emitters. What a pain!
More work in the garden today, setting up the second section of the sprinkler system. As I
had expected, that took longer than others might have expected: getting the positioning of
the sprinkler emitters is quite tricky, not helped by lack of adequate documentation. The
documentation on the Philmac web site doesn't seem
to relate to what they sell, and the only information on the wide sprinklers was that they
had a sprinkler radius of 3.5 m at 150 kPa.
What I found was different: the pump was cycling between cut-in pressure of 220 kPa and
cut-out pressure of 350 kPa, and the radius was closer to 2.5 m than 3.5 m. Do I have that
much head loss in the system? Maybe; a pressure gauge would be interesting. That would also
mean a maximum run for the 19 mm low pressure poly that I'm using.
Learnt a positive thing too: it's trivial to move sprinklers around, so did a fair amount
of that. Now, of course, I need more sprinklers. That'll have to wait until Monday.
Then I on to buy more fittings for the sprinkler system. Somehow the smallest details take
up the most time: one run of the pipe will go along the base boards around the outside of the
house, and I need to screw clamps to them. Simple enough, and I had no difficulty finding the
clamps ($0.25 each in metal, $0.35 each in plastic), but what screws do I use? The
salesperson at the hardware shop recommended screws 40 mm long, which would go right through
the board. That seems a little excessive to hold a 2 metre length of plastic pipe that will
weigh about 300 g per metre when full of water. And then there was the question of corrosion
protection: zinc plated, galvanized (yes, there appears to be a difference, probably the way
the zinc is applied) or “golden”? In the end, disregarded the advice of the
salesperson and bought some zinc-plated screws 12 mm long.
On to Midland Irrigation to discuss the throw length of the rotor sprinklers (supposed to
be 7 m, is 5 m). It seems that the rotors require a pressure of 300 kPa, while the jets
require 150 kPa. Why do they make different fittings with such drastically different pressure
requirements? They work at the estimated 200 kPa that I have in the system, but my distances
are all wrong.
Spent much of the day adding sprinklers to the system, and now I have everything set up
that I had planned for the first stage. There will be more when we know what we want to do
with the space to the south of the house, which currently looks like this:
More work in the garden, which kept us busy most of the day. At least we now have some things
planted, nearly all of them cuttings from existing plants in the garden (the only exception
was the bulbs that I had exchanged last month.
It's my guess that this is the day we planted
and Dianthus to the west of the garden
Despite multiple attacks with glyphosate, weeds still continue to come up, so put in a layer
of old packing cartons with only holes for the plants:
Some of the plants show remarkable ability to grow from cuttings. Last Friday we had to prune a number of bushes in the north bed, including
a succulent that blooms bright red in spring (and maybe longer if
it gets enough water):
I have no idea where the pipe running to the top of the photo comes from; it's the same
kind as the stuff I have been laying, but it was there already, and I wasn't aware of either
end. This will document it.
The grub is one of many I've found in the ground; they're about 3
cm long. I wonder if they're beneficial.
On the way home dropped in at Avalon Nursery in Haddon to look for a couple of Callistemons (or is that Callistema?).
Left after spending far too much money with two Grevilleas, a Kaffir Lime tree and a
strange-looking plant calling itself Sapphire Dragon, which proved to
be a Paulownia kawakami (or is
that Paulownia kawakamii? Googlefight seems to
think so), which on the photo looks something like an enormous jacaranda.
By the time I got my camera one of them had burrowed away.
I'm still trying to come to terms with the necessity of having to dig up the entire 300 m˛
of garden to suppress the weeds. In the meantime, decided to clean up the ground cover under
our mystery yellow flowering tree. The immediate ground cover the “succulent
daisy” that we've planted in many places. One of the disadvantages is that old growth
dies and new growth comes up over it, getting weaker as time goes on. There were also a
couple of bearded irises in the area, so I decided to remove everything and start again:
Last month it was really warm, but things have changed. The following graph shows the
ambient temperature in the brewing shed over the last 2 months. The extremes are probably 5°
either side of this value, so the maximum on 16 March was round 40°, while the minimum today
was round 0°:
Did some work in the garden anyway, mainly digging. I'm wondering how many of the things
we had intended to transplant would actually survive at this time of year; we might be better
off preparing the soil and transplanting in early spring, when there are no more frosts.