Netting Brassicas

In Perth these little critters can turn your much loved brassicas in to lace. In seasons passed I've totally given up on broccoli and caulie crops because of them. In other parts of the world where its cooler frosts kill the moths and people are advised to wait until its really winter to avoid them, but here we have them all autumn, winter and spring. Bastards. 

We've tried a few hippy solutions like leaving egg shells or bread ties on sticks to repel the moths to no effect. I've sprayed with Success before and it does work pretty well, but I've been keen to try a greener solution - that works! And here it is...netting them. I was so impressed with our apple netting last year, surely this will work to keep cabbage whites off the barrassicas. I used an old mozzie net that we never bother using and tied it up to the grape trellis. I weighed it down with bricks, but you could just as easily peg it.

It might look a bit strange but I really reckon it will work. The only problems I foresee is that:

1.  I may have been a bit late and there might already be eggs on the leaves that hatch in to hungry little caterpillars 

2. It might shade the plants too much. Even in winter Perth is pretty sunny so I'm hoping that it might just slow them down a little. 

3. I have to move the net to do any liquid fertilizing and (hopefully) to harvest my bountiful unblemished broccoli. 

But its worth a shot. We love broccoli!

Blue Boogers

Quincey loves Scitech so Ads dutifully took him there this last school holidays. They watched a slime making demo and, lucky for parents, the recipe is online! But here are the basics:

1. Dissolve 5 g Borax (approximately 2 level teaspoons) into 100 ml warm water
2. Dissolve 3 g Guar Gum (approximately 1 slightly heaped teaspoon) into 150 ml warm water
3. Add 1 tablespoon of glycerol/glycerine to the guar gum solution
4. Add 3 drops of food colouring to guar gum solution.
5. While stirring, slowly add borax solution to guar gum solution. You will only need to add 30 – 50 ml of the borax. Continue stirring until the solution thickens!
6. Experiment with different concentrations of borax and guar gum solution to get different sorts of sliminess

It's exactly the same stuff I used to purchase when our parents let me and my cousin loose at the shopping center on my school holidays: Ghost Busters slime. The kind of slime that feels wet and doesn't stick to your hands but will totally ruin carpet. 

Awesome! We love it!

We made up a batch for Quin and a batch for a birthday pressie and I thought to myself, this is something all children should enjoy. So I think Quincey's next birthday party will be a slime themed party and we can make some up for all the kiddos so they can go home with slime instead of a landfill starter kit lolly bag. It's cheap, easy to make, minimal packaging and rates super high on the gross out/fun factor. Until it gets into the carpet. But kids are only kids for a short time, nice carpet is for retirement not parenthood. 

Going green: what's the payback?

Going 'green', or installing technologies which lower your footprint, is mostly done by people who are interested more in saving the planet than saving a dollar. This certainly applies to us. The perception for many is that being green is more costly, so I thought I'd show you how going green has lowered not only our ecological footprint but also our bills.

When we recently installed a grey water system it made me reflect on all the things we've done in the last five years. These include solar PV, rain water harvesting, solar hot water, cargo bikes and grey water. I added up the costs of the above and it came to $33,500, which is a lot of money. But how much will these technologies save us in the long run? Well, here are my best estimates:

system	cost		savings per year		payback (years)
PV	$6,500		$600		10.8
solar hot water	$3,500		$300		11.7
rain water	$10,000		$100		100.0
grey water	$4,500		$50		90.0
cargo bikes	$9,000		$5,000		1.8
Totals	$33,500		$6,050		5.5

There are some surprises in there and I'll explain each one.

First, PV. We have a 1.1 kW Kaneka thin film solar PV system. It generates more or less what we consume (4.5 kWh a day) and we feed in 75% of what we generate to the grid. We are lucky enough to qualify for a now defunct feed in tariff, which means we get paid 48 cents a kWh for power fed to the grid. This makes our bills around -$60 a year (credit) and our bill would be around $550 a year without PV, so we save around $600 a year. This means the system will pay itself off in about 11 years and after that we'll be saving money for another 15-30 years. This was obviously a good investment of $6,500.



Our solar hot system (a Solahart 180L thermosiphon system), cost $3,500 two and half years ago and it saves us around $300 on our gas bill. We boost a little bit between May and October, but this only costs us $20 a year in electricity. The payback time is very similar to PV.

Water is so cheap in WA that there is no way our rain water or grey water systems will ever pay for themselves. Both systems were quite expensive ($10,000 and $4,500 respectively). The 14,000L tank needed lots of digging and piping, new gutters etc to install and is piped into everything (whole house and retic). The Grey Flow system was less expensive and feeds a lawn and fruit trees.We harvest 70,000L of rain water a year and probably about 50,000L of grey water and you can see that the savings aren't great. However this isn't a big deal for us since we see these technologies as more of a society benefit than anything else. The more water we can generate the more water there will be in the dams and the less the need for desalination and ground water use (and the less power used to pump them around).







The bikes have almost paid for themselves already. How can that be I hear you say. Well thanks to the bikes we got rid of our second car, which cost us at least $5,000 a year to run. These are not your average bikes, they're both electric cargo bikes (one is a Bakfiets long, the other a retrofitted electric Workcycles Fr8). They're dutch and they'll probably last longer than me. They get us to work, to the beach, shopping, school runs and more.

So the payback time for all this is five and a half years, not bad eh? Obviously payback times will be different for everyone, depending on the costs and savings involved. However this shows quite clearly that going green can save you lots of money, especially if you invest in areas where you get the best bang for your buck.

Plastic free triumph

It's mandy season and Quincey is sucking them into his growing body by the kilo. I can't keep up with his appetite for them. I am spending my waking hours gathering up little piles of peel from all over the house - kitchen table, bathroom sink, bed (his and ours). 

I do love his fruit bat ways but trying to be plastic free and feed the family is challenging. A few days ago I was shopping at our little fruit and veg shop and feeling a little annoyed that all the best fruit (as in the cheapest, freshest, and best size for lunch boxes) are always in plastic. In this case really nasty net plastic. Imagine what that could do if set free in the ocean. 

But Being the fallible human that I am I thought, 'bugger it' and bought three bags of fruit. When I unpacked them at home I found that I could just untie the top and not rip the bag. So I kept them. Of course I had to go back to purchase more fruit today and I took my three plastic net bags back. I asked the fellow on the checkout if he would reuse the bags and he said he would. No probs. He even joked about giving me a 10 c discount! Wonderful! So I bought more mandies and just unpacked them on the counter but not in an agro, protesty way, in a cheerful, 'oh yes, there is too much plastic around' kind of way. So I get to purchase the best fruit, the shop gets to reuse their bags and I feel virtuous about  walking out of the shop without a scrap of new plastic (the bag in the picture is old and well loved!). And I make a new friend! 

Costa visit

Costa Georgiadis (the main presenter of Gardening Australia) was in WA last week and paid us a visit. It was great to show him around the garden and have a chat. Here he is speaking into the Banksia microphone!

He was just how comes across on TV, very bubbly, animated and warm. And he really gets it, sustainability that is. He's really into behaviour change, Plastic Free July, etc.

 And the beard, what can you say except Respect. There's probably enough microbial activity in there to keep the whole planet going!

He really is a garden guru...

Mango planting

I planted a mango tree out the front this week. It's a Kensington Pride (aka Bowen) grown from seed. Here's how I've set it up. First I dug a big hole and watered it for 30 minutes to saturate the super sandy soil. Then I mixed in some cow poo, sheep poo, rock minerals and bentonite clay. Then I planted the tree with a bamboo stake.

Then I set up the retic. Mangos are tropical plants so they need lots of water so I've set up a 'thirsty' retic station using a disused station which we used to establish the native garden. The others plants I'll put on this station are the Macadamia, bamboo and yet to be planted Avocado. I've read in my fruit tree bible (Louis Glowinski's Complete Book of Fruit Growing in Australia) that bearing mango trees should not be watered for three months before flowering. So I put a valve in the line so that I can still water the other plants but not water the mango tree. I've also left a line available for growing sweet potato close by (another tropical plant).

Young mango trees like some shelter, so I’ve banged in four posts to support clear poly film for winter. This will provide a warm micro-climate for the tree in the cooler months and protect it from wind. In summer I’ll replace the plastic with shade cloth in order to protect it from the heat. After a couple of years of this the tree should be able to fend for itself. I’ve thought of laying some thermal mass (eg dark rocks) around the tree to adsorb warmth in winter, but this will have to wait for another day.

In about five years we should be harvesting our own mangos. Yum, I can’t wait. Whether I’ll be able to actually eat any before our very own fruit bat (Quin) gets them remains to be seen…

Solar year 5

It's five years since we installed our solar PV system (a 1.1 kW Kaneka thin film grid connect system). Ever since then our goal has been to generate more power than we consume and after four years of achieving this we have not met our goal this year. The pattern of usage and generation was very similar to past years, with higher consumption and lower generation in winter, transitioning into higher generation and lower consumption in the warmer months.

We came pretty close to our goal, generating just 44 kWh less than we consumed (about 10 days worth of generation). Although we took a lot from the grid, we also fed in three quarters of the power we generated to the grid. We are lucky enough to qualify for the 48c feed in tariff (FIT) so this makes our bill really low (a credit of $67!). If we didn't have solar panels (BAU, business as usual) our power bill this year would be $552 which means we saved $619 this year. Since our panels cost around $6,000 five years ago this means the payback time will be roughly ten years, which isn't too bad considering we should get another 15-30 years life out of them. We saved a grand total of 46 cents with smart power this year. This is a system whereby you pay different tariffs depending on the time of day you take power from the grid. There is very little point in having it now if you get the FIT but we'd need to pay $60 to remove it so there's no point right now. 

kWh generated	kWh taken from grid	kWh fed into grid	kWh used	Average daily usage (kWh)	Average daily generation (kWh)	Year 5 bill	BAU bill	$ saved with smart power	% of power generated fed to grid
1619	1281	1237	1663	4.57	4.45	-$67.34	$551.89	$0.46	76.4

So why did we use more power than we generated this year? There are a few reasons. As solar panels age their production tends to drop off slightly and this is one of the reasons we didn't meet our goal this year. The chart below shows our average daily generation and usage in the last six years. Our generation has gone from 5 kWh in year 1 to 4.7, 4.8, 4.5 and 4.45 in subsequent years. As a matter of interest here are the average daily amounts of power generated by our system each month over the last five years. Being in the southern hemisphere means our summer is December to February and this is when we generate the most. Spring is the next best season, then autumn and winter last. The main reason for this is the number of sunny hours per day which is highest in summer. Perth has a mediterranean climate, with hot dry summers and cool, wet winters. This means that winter days are often cloudy which leads to low solar radiation (and they're also shorter of course). PV panels actually perform at lower efficiency above 26C, which we regularly get in summer. So this means that the longer and sunnier days in summer more than make up for the lower efficiency of the panels in high temperatures. We also get some shading of our panels in winter, which helps explain why June and July are so bad.  

Our usage has gone from 6 kWh in year 0 (before we went solar) to 4.7, 4.4, 4.3, 4.5 and 4.6 in subsequent years. We've done really well in past years to use less power despite adding new power users (eg solar hot water booster, rain water tank pump, electric bike charging) but this year we simply couldn't do it. We bought another electric bike (the Fr8) and recently installed a grey water system which uses a small amount of power to pump the water out. These two additions coupled with lower generation this year made it too hard a task. We still did very well considering the average usage for WA is around 18 kWh a day, four times what we used.

But never mind, we're hoping to turn this around next year. Our 15 year old washing machine just died so we've bought a new super efficient front loader to replace it. This may make the difference next year so watch this space.