The net effect
So last year we used the flimsy white nets you get at the hardware store to protect the remaining 5 bunches of grapes, as well as all the berries. But we learnt at a permaculture/apple workshop, which was run at Diggers nursery, that in the long run permanent nets are more cost-effective. Besides, they are much easier to work with, under and around. So last year we got the good guys from Jochim Family Maintenance to put up permanent nets over two established peaches and an apple that grow close together. They did a real stunning job as you can see on the photo below.
This year when I called them, they took a few days longer than usual to respond, and in that time mr. impatient had made up his mind to wing it alone – besides I thought it would save us some dollars too. But I had no experience (nor tools) working with steel or wire, never mind the two combined with massive nets.
Although the plum trees along our 100m long driveway “orchard” are going to ripen first, I decided to use the grapes for my learning curve and prototype. The reason for this was straightforward – the grape trellises are significantly lower than the height that we need for the fruit trees, the overall length of net required is about 1/5 of the driveway and I could do it with a much simpler design. So it was an obvious choice where I could cut my teeth (and many lengths of galvanised pipe).
I had 5 lengths of 40mm (32nb) galvanised pipe left over from the previous exercise, and even though I wonder if it isn’t overkill, and whether square tubing wouldn’t be easier to work with, I carried on with the galvanised pipe. I drew a few rough sketches and set off to get my supplies. At each of the suppliers (they’re all listed on the Resources page) I got a bit more advice, learnt a little bit more and continually refined my design. Steep learning curve is an understatement!
In order to learn how to tension wire using a Gripple tool, I first fixed the fence between us and the school behind us, which was damaged when a huge Eucalyptus tree blew over a year ago. Got that little task off the back-burner list too!
There were a few interesting challenges with the grape nets project. Climbing a ladder while balancing a 6.5m length of galvanised pipe was an intensive exercise! Installing a 16m x 10m net length-wise only 10cm away from a barbed wire was interesting. Fortunately there was a hard onshore wind blowing – good, so I wasn’t missing any good surf. No, in fact, I could actually use the wind to help me by blowing the net over the steel frame, away from the barbed wire.
I used separate sheets for the two open sides, so I didn’t have to bundle up large sections of net around the corners, which I think led to a neater result. This meant though that I had to affix the zippers on to the edges of the two separate sections of net. It is normally easier to fix the zippers to a “closed” section of a single net and then cut the net afterwards where you open the zipper. Anyway in the end I got it done without getting any wire staples into my fingers!
Once the “prototype” was completed, I went straight on to the driveway. This was an order of magnitude bigger project. I actually drew up a more detailed schematic and a full cutting list. The local hardware didn’t even have enough bags of concrete for the posts!
I spent two full 10-hour days just doing preparation work – measuring and marking, cutting sections of galvanised pipe and drilling holes through the hard steel. The first day I drilled 160 holes through hard galvanised metal pipe, followed by 254 holes on the second day if I counted correctly. Dug 20 holes in the hard clay ground (with a post digger). Planted 20 x 3m posts. Carried and wheelbarrowed sections of pipe and fittings to their correct places. Pre-bolted many halves of the T-joins.
For the actual assembly of the five frames I rented a Snorkel cherry picker. No way was I going to assemble the A-frames on top of the posts while balancing on the top rung of a ladder wobbling on top of uneven mulch. Unfortunately that day I worked round the clock to get the hardest part of the job completed in the time we had the machine – to the extent that we didn’t take a single photograph. Markus (now 9½) assisted me by managing the stabiliser legs (a slow and painful process to set them out and retract them again) while I did more pre-assembly work using the ladder. He jumped into the basket for 3 of the 5 frames and I must say he managed to manouver it quite well without wasting any of our precious time. Pity we don’t have a photo of him in action.
After a two-day break (Sunday + one day on my day job) followed a day of spanning, fixing and tensioning more than 700m meters of wire to anchor the frames and to complete the wire framework on which the nets are hung.
Finally came the fun challenge of draping and fixing four 15 x 10m nets. The first day was a blistering 35C with a hard dry Northerly wind, which blows the nets straight onto the barbed wire between us and the neighbours; so I only did one section that day. But in the process I figured out a better way to unravel and straighten the nets before hanging them, as they come packed stretched tightly diagonally. I also wanted to see how the wires take the nets in the hard wind. They sagged a bit too much to my liking, and I was concerned that tensioning the wires even more may pull the posts skew in the ground.
The following two days I did the rest of the nets with the assistance of the onshore breeze again. The third day I installed the two end sections of net – 3meters each side. I also installed 8 zippers along the long side, which will enable us to roll up the four long sections to work in there or to keep rolled up when the trees are not in fruit. All the nets can be rolled up to clean underneath and to keep the weeds out of the nets during the winter season.
Comments and lessons learnt
Installing nets at this scale is a big job – it took quite a few “man days” to get the job done. It’s definitely not a quick one day job!
In retrospect I think the decision to wing it with the nets was a good one. My nets may be a little skew and crooked here and there, but I acquired a few useful tools and in the process I learnt a hoard of new skills:
- Cutting and bolting galvanised pipe in various ways, using straight Ts, U-bolts and wire.
- Spanning and tensioning wire, including various ways of affixing it to the metal frames.
- Pre-stretching, installing and fixing the permanent nets themselves, including zippers.
Besides, as part of our quest for self-sustainability, one has to learn to operate outside your comfort zone.
Fortunately we don’t even have a serious cockatoo or possum problem. Some guys have both of these – they have to put up even more sturdy and secure nets.
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