Wednesday, December 16, 2015

hot, hot, hot...

Here in Adelaide, we're in the middle of our third 40C+ heatwave for the summer (which only technically started 17 days ago. I think a good case could be made for starting summer on October 15th in Adelaide). It has not been a hot spring overall, but we have had some very hot weather and have had very little rain. According to the BOM, Adelaide had only 15mm of rain in November (I would have guessed less!). October was hot and dry too, with an average maximum of 27 C (compared with a historical average of 21.3 C) and only 9 mm of rain.

Today, I went out in the garden at 3:30pm. It was 43 C, and we're in our 3rd day of a 5 day heatwave. Here are some photos I took.

2 year old walnut tree, showing dead burnt leaves from our last 40 C + heatwave. It will lose more leaves after today -- notice the wilting present on its leaves.
2.5 year old apple tree, showing burnt apples and wilting of leaves. I hope that, as the tree gets larger, it will shade more of its own apples and reduce the burning.

tomato plants in a non-wicking bed. They are very stunted, with lots of wilting and burnt leaves. We have been harvesting fruit, about 1 kg so far, but there's not that much fruit there. I think they need more water than I've been giving them (about 2 times per week)

I showed these images partly to show the effects of Adelaide heat waves, but partly to contrast with the wicking bed photos below. Note that neither of the wicking beds have been watered for 5 days, and the average daily maximum has been about 38 C in that period.

The better (and older) wicking bed. There is a little bit of wilting on the zucchini, but remember -- it's nearly 43 C outside! As you can see, the plants are blooming.

This is one end of the newer (large) wicking bed, that leaks a bit. But it still is working, as can be seen from the very happy curcurbits and beetroot shown here.

The other end of the large wicking bed, showing more happy curcurbits (with no signs of wilting) and happy silverbeat.

So, the wicking beds are an absolute, resounding success. I had been thinking that we wouldn't want more, because giving tomatoes too much water leads to poorer fruit (because the plants don't grow such extensive roots). I now think that we definitely need a wicking bed for tomatoes, but that we'll just keep it drier than the other beds. I think eventually, all our annual vege beds will be wicking beds.

Grey water project

In a previous post, I described a grey-water system to process the washing machine water. This is a failed project. I used 25 mm poly pipe to send the water, and I knew that it would block. I assumed I would be able to just blast it through with high pressure water to clear it. Unfortunately this doesn't work. I don't know if this is because
  • the pressure isn't high enough
  • the blockage is too intransigent, or
  • the pipe is just too long (15 m)
or a combination, but it is just not working so I've abandoned it. For now, our washing machine water is just going down the drain.
What I plan to do instead, is dig up some weedy reeds we have near the fence (which is only about 3 m from the laundry), and pipe the washing machine water there, and plant some bananas there. I'll do this with 50 or 70 mm PVC. Anyway, we'll see...

Secondary glazing

This is a success, and the house has performed well in the hot weather. We've run the reverse cycle A/C split system (a 2 kW system, so not particularly large), to try and keep the living area cooler while our solar PV is producing, and the temperature in our bedroom has stayed below 30C, which is quite bearable with the ceiling fan on low. Having the washers around the screws means that the acrylic sheeting stays sealed around the sides of the window.

1 comment:

  1. Hi Angus,

    Mate, I feel for you. It is almost 10.30pm here and it is still almost 24-25'C, so I can't imagine what is going on in Adelaide. Just some thoughts for you:

    Walnuts are very drought hardy, but only once established - until then they need heavy composting and lots of water every day (or maybe a bucket every few days for a decent soak). Most of the nut trees here require to grow as an understory tree in the shade.

    Sorry to say it, but the apple is in the same basket. I've written off a few first year fruit trees this week too.

    You have tomato fruit already? Wow. Here, they need water every single evening after the sun has gone down so that it gives the water a chance to penetrate into the ground. Plus mulch / compost mix (they're forest edge plants).

    The wicking beds look awesome. Top work and great observation.

    50mm pipes are what is used in bathroom drains and they get clogged over time too. Would you consider 90mm storm water pipes? I've never seen one of them clogged. If you splash out a bit more the 100mm sewer pipes (the same stuff really, just bigger) are even less likely to get blocked.

    It's 27'C inside here and the whole house is open (with insect screens) and it just doesn't seem to want to cool down. Tomorrow night is meant to be a shocker, but then a monsoon is predicted for Sunday (fingers crossed).




Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.