Sunday, July 12, 2015

Bog garden filled ahead of schedule!

I got a lot more done today than I expected – the bog garden is now filled with soil and resting. But I was not counting on getting it to this stage because of the weather forecasts.


For the past week, the Australian media have been hyping a low pressure system, dubbed the “Antarctic vortex” or “snowmageddon”. Despite forecasts predicting heavy rain, damaging winds and even snowfall here in Canberra, it was pretty much a non-event. We had a brief storm out of it that dumped hail for 15 minutes or so (see the white slush inside the trailer) and that was it. Although I have to say it was bitingly cold outside today (at least by Australian standards). When I saw it was actually pretty clear outside this morning, I got to work. The last things needed before filling with soil were a filler and an overflow. The fittings I used for the first bogs were not great, so I wanted to get them right for this last bog. So off to Bunnings (= Lowes)…


Here is the filler tube all set up. I ended up using 90 mm PVC pipe because it supported the best range of fittings. The filler is capped with a special screen for excluding mosquitoes, which means I will not need to use gravel in the filler to keep mosquitoes out. The filler has a 90* end at the base that opens into a manifold allowing you to connect 90 mm PVC to ag pipe. The fittings are mechanically fastened together.


This is the overflow tube. I had wanted to use something like this for my first bog gardens, but run out of time and ended up not using an overflow to start with, and then a substandard retrofit. This design has a vertical tube that is inserted through a hole cut in the ag pipe, and uses a tank outlet manifold to pipe water out of the bog. This design allows the junk that accumulates at the bottom of the bog to be flushed out. I used a T-fitting because I have an idea that will allow me to easily drain out the bog when it gets too wet in winter. Note I also zip tied the stocking over the ag pipe onto the tube to prevent peat being flushed out accidentally.

time to fill

With all the plumbing in place, its time to fill with CP substrate.


I’m using 1:1 peat: sand for the substrate. I mixed the first batch in a wheelbarrow but ultimately ended up mixing it with a shovel in the bog itself.


Finally - here is the bog, filled with substrate and flooded. Note the overflow in action. The taller pipe above the overflow is part of a design that will allow me to convert it to an automatic siphon. We get a lot of rain here in winter, so I am often having to drain out the bogs with a length of hose. With this design, all I need do is fit a end nut over the tall tube to seal it off and screw on a hose fitting to the overflow. Once the pond is full, it will automatically create a siphon and discharge itself down to the ag pipe level. That, or I need just attach the hose and suck to prime the old fashioned way. This is a lot easier than having to insert a length of hose into the ag pipe every time I want to drain out excess rainfall. In summer, I will leave the end nut off so it will overflow without draining itself completely.

I will now let the new bog settle over the week. It will be rather sloppy for some months yet; the last bogs settled once the Sarracenia put out new roots and really only became established midsummer. I hope to get it planted out next weekend.

Until then, good growing.