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Peta’s Artichoke, Fennel & Blood Orange Salad with Apple Aioli

PetaA long-time fan of Kay’s work, when Peta Mathias found out about Koanga’s fundraising mission she wanted to know what she could do to help. Not only will she be introducing Kay in Auckland on the speaking tour, Peta also sent us this recipe for our organic heritage artichokes, alongside our old favourites Florence Fennel and Giant Geniton Apples.

artichoke purple de jesi

Artichoke, Fennel & Blood Orange Salad with Apple Aioli
(For 4 people)

For the salad:
500g fennel bulbs
4 blood oranges
8 baby artichokes or 1 X 390g tin artichoke hearts in brine
100g black olives
extra virgin olive oil
sea salt and freshly ground black pepper
cup of fresh mint, torn but not chopped

1. Trim the ends off the fennel bulbs. Cut in half and cut tough hearts out in a V. Slice finely and immediately place in lemon water to prevent browning.
2. Take one orange and zest half of it. Peel it and the others, removing all the pith. Slice.
3. Cut the baby artichokes in half, scrape out the hairy choke with your finger and boil for 10 mins in salted, lemon water. If using tinned artichokes, cut in half and drain well.
4. Remove the olive stones with an olive stoner and sauté them in hot oil for 5 mins.
5. Drain the fennel well and toss gently with the oranges, zest,  artichokes, olives, salt, pepper and mint. Pile up on a platter and squeeze lemon juice all over. Serve the apple aioli on the side. A glass of Lombardi Sauvignon Blanc to wash it down with would not go astray.

Apple- Giant Geniton- MM106 R/S

For the Aioli:
4 cloves of garlic, chopped
1/2 tsp sea salt
2 egg yokes
1 tsp Dijon mustard
500 ml extra virgin olive oil or 1/2 olive 1/2 vegetable oil
lemon juice
a small tart apple, peeled and diced
1. Mash the garlic and salt salt together with a mortar and pestle.
2. Stir in the egg yokes and mustard with the pestle then gradually add the oil drop by drop.
3. When half the oil is in add a little lemon juice and warm water and continue the stream of oil, stirring with the pestle till all is incorporated. This can be done with a food processor or hand beater.
4. Taste for seasoning and stir in the diced apple.



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Kokako’s Urenika Potato and Quinoa Salad with Capsicum Aioli

cooked urenika22-1-09 015
The Urenika potato was the first Maori potato in Koanga’s collection. It is long and tubular with dark purple skin and flesh, which retains its colour beautifully when cooked. The Urenika is part of our potato trial where we are endeavouring to turn-back the deterioration of New Zealand’s organic heritage potatoes, which have been shrinking in size and losing resilience over the past 20-years. Read about our potato trials for 40-odd NZ organic heritage varieties here.

This Urenika Potato and Quinoa Salad with Capsicum Aioli recipe has kindly been shared with us by Kokako organic cafe in Grey Lynn Auckland. It tastes best when you grow the ingredients yourself  -get your seeds  here.
Serves 4

Salad ingredients
• 500g Urenika purple potatoes (cut into bite-sized pieces)
• 150g red organic quinoa
• 1 courgette (cut into small cubes)
• 10g red onion (sliced very finely)
• 50g green beans (cut into 2cm lengths)
• 10g pinenuts
• 5g chopped spring onion
• 5g chopped parsley

Aioli ingredients
• 25ml extra virgin olive oil
• 125ml canola oil 
• 1 egg yolk
• 1-2 garlic cloves
• 1/2 red capsicum
• 1/2 tsp whole grain mustard
• 1/2-1 Tbsp cabernet sauvignon vinegar (or any kind of red/white wine vinegar)
• salt and pepper to taste
1. Prepare the salad ingredients:
– Boil the Urenika potatoes for 10-15 minutes until sufficiently cooked.
- Cook quinoa in boiling water for 10-15 minutes.
- Sauté courgette until lightly caramelised.
- Spread pinenuts on a baking sheet and bake at 180°C, stirring occasionally, until golden-brown, which should take 5-10 minutes.
2. Prepare the aioli:
– Sauté or roast capsicum until nicely cooked, put aside to cool.
- Place egg yolks, mustard, vinegar, capsicum, salt and pepper in food processor.
- With the motor running, add oil in a thin, steady stream until the mixture emulsifies and thickens.
- Taste and add more seasoning or vinegar if needed.
3. Place all vegetables in a bowl and pour the aioli, toss gently. Taste and season if needed. Sprinkle over pinenuts, parsley and spring onion.

quinoa temuco amaranth ptQuinoa



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Koanga/Kotare/Earth Lament


Rachel has lived at Kotare Village (home of Koanga Institute) for six months and is event coordinator for Kay’s speaking tour.  She has shared a blog with us from her own site Mummy Never Vacuums.

….It is beautiful here in the valley today.  After two weeks of rain, and rain, and rain, finally we have clear skies.  Tonight it will be cold.  Yesterday, in the rain, we held a working bee at Tes, Shaked & Mel’s camp.  A baby will join them in a couple of months.  Through downpours we scraped the old paint off their bus in order to repaint and make it waterproof.  We cobbed the newly built rocket oven into their kitchen teepee, cut slabs to build bridges over the parts of the path to the shared ablution block that are already knee deep with water and mud and made ferments to add to their food stores.  Today at our house, in the sunshine, the momentum continues.  Tomatoes and their metre deep in the ground stakes, are pulled out.  Wheelbarrows full of weeds and dead plants and carbon crops are taken to the compost heaps.  Brad plants seedling after seedling after seedling.  My three year old brings me an arrangement of zinnias and shows me where the seeds are.



Yesterday, today, tomorrow, we work, for the Institute, for ourselves, for each other.  As our funding deadline draws nearer, our work is tinged with sadness, stress, at moments despair.  We plant crops and know that we may never harvest the seed, that we may never eat the produce, but we cannot stop and see what might be, for all that leaves us is cold, malnourished, bored and without hope.

Plums- Black Prince- Peach R/S

We love it here, all of us, and the work we do is more important than most people will ever know, until it is too late.  We save seeds, and we sell them so we can afford to save more seeds, but that is just a tiny aspect and a narrow view.  We preserve biodiversity, integral to the survival of ecosystems.  We build nutrient density and resilience into our crops and our livestock.  It is not something that happens overnight.  Three years of hard work have gone in so far, of research and application, of trial and error, of wins and losses.  Of bed preparation and double digging, double digging, double digging.  Even if we can move and plant seed elsewhere, it is such a huge set-back to start all over again.  And who knows if we will be able to start again?  Where will we go?  How will we get there?  Kay is in her 60s, and I know she has the energy to keep going here at Kotare until she drops, but I don’t know if she can pack it all up and start afresh elsewhere.


And we are more than seeds and plant material.  We have our eyes wide open to the state of nature and the part the human race plays in it.  Nature is not something separate from us, we are one.  Nature is not something that we can fence off in zoos and national parks and say: “it’s ok, we’re preserving nature over here, we can go ahead and pillage the rest of the world of it’s resources”.  “Resources”: a word we use to separate the natural world, the ecosystems, from human desire and greed.  We put fish in a marine park, and they are ‘nature’.  We leave them in the rest of the ocean, and they are ‘resources’.  It is not that simple.  We want to preserve nature and ecosystems because we are as much a part of them as the glaciers and the kiwis and the orangutans and the totaras and the grasshoppers.  We want to preserve nature because we want to preserve US.  When we rape our earth of it’s minerals, ore, oil, trees, water, fish, meat, SOIL & CARBON, we aren’t just depleting resources: we are committing suicide.


We know that peak oil has long passed.  We know that drawing near is the time when the energy invested in producing oil will exceed the energy returned.  We know renewable energy sources will never live up to the expectations of the world’s current energy usage, will not even come close.  We know we need to find every way possible to consume less and generate more.  Here at the Institute, we strive to do that, every day and in every way.  We are by no means perfect, because like the gardens our regenerative process here is only three years old, and there is always more work to be done than there are willing and capable hands to do it.


The majority of Institute staff work for minimum wage.  Some work for short periods for nothing, and the rest are somewhere in between, mixing voluntary hours with earning enough currency to survive in the wider world.  Cars still need petrol and WoFs, mail still needs postage stamps.  My family earns minimum wage for 30 hours per week and volunteers many more.  It is enough to live a simple and happy life.  An existence where the reward is contributing to a cause that is worthy of our commitment and living in a way we love on land that we love with people that we love.  We want for nothing except the future security of our land.  I married my husband here.  My son took his first steps here, in Tes and Shaked’s bus.  My daughter leaps out of bed every morning and begs her father to take her out to work in the garden.  We have a community here who are like family to us.  We eat together daily, we grieve together, celebrate together, support and heal and nourish each other through the good times and the bad.  Like family we have moments of sheer joy where we love the pants off everyone, and periods of utmost irritation and annoyance where we can’t bear to be around one another.  We love this place and all there is to it.  We can’t bear the thought of leaving.  That thought is a throbbing undercurrent to our days now.  We could have as little as three months left.  Surely someone will understand, will see what we see, enough to give us the funding to stay here and keep the Institute running.  Surely.  We’re not yet ready to give up hope.



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Kay’s Garden Blog, April 2014

I’ve found it really interesting this Autumn watching myself… We are so, so busy preparing for our national speaking and workshop tour, there is absolutely no time for gardening… Being able to buy this land is so critical for the future of the seeds, the trees and work of the Institute that we have all had to focus on the fund-raising effort…  but I found I couldn’t do that until my garden was planted.
Somehow there is a sense of peace and completeness that comes with a well planned and planted garden… and we’re praying we will still be here to enjoy the fruits of our labour.

bread and butter pickles lacticTollies Sweet

I’ve been making lots of ferments that will last all winter now, carrot and ginger, carrot and perilla, garlic, carrot, beetroot, daikon and onions… all the roots, and a great drink mix we love: beetkvass. All of the recipes are in Change of Heart.
I’ve also just harvested all of the remaining peppers and roasted them and am now fermenting them in a 10% salt mix which will make a fermented pepper sauce to add to all our soups and stews over winter.

9.12.10 032
The entire 200sqm garden is now planted and bedded down for the winter, a little late for here, but done now.
Half of the garden is in carbon crops, mainly oats and lupins.
A quarter is in roots and legumes, beetroot carrots, daikon, turnips, Tic beans and broad beans, and the last quarter is in the heavy feeders: 20m of brassicas of all kinds and days to maturity to ensure a constant supply, Ruapehu caulis – amazing things, Dalmation cabbage -my cabbage of choice because of the high nutritional levels, Brussel sprouts, Purple Cape cauliflower -also because of nutritional levels, and Borecole -my favourite kale, also super nutritious.
Another 20m of the 50 in the heavy feeding section is in all of our onions and garlic. I’m working towards the most nutritious of everything and the easiest to grow. Right now this list includes Multiplying Spring onions which we eat daily, Welsh Bunching onions also eat daily, way more flavourful and nutritious than modern large onions, multiplying leeks (they are an experiment still, if I can’t get them bigger this year I’ll probably abandon them and go back to leeks from seed) loads of shallots, which grow large and keep well if grown in good soil with the right minerals, and are more nutritious than large modern onions. It is a lot easier to plant shallot bulbs and keep some to plant again than growing onions from seed.
The last 10m bed is in winter greens, rocket, Winter lettuces, Red Coral mizuna, Upland cress, coriander, celery, parsley etc.

multiplying spring onions17.9.09 153I’ll just have to keep the weeding up while it is still warm and they are growing so hopefully by the time we leave here in mid May on our tour, it will be cold enough that their growth has slowed down.
We’ve had another soil test done and that has been encouraging but I want to spend a lot more time talking about the soil journey and the compost journey which we are very excited about… next time…
See you at a town near you, with all of your friends, over the next couple of months on our journey.
Arohanui Kay

Craggy Range1.12.10 089

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Summer in the Orchard

(from left) John, Gail and Bob
(from left) John, Gail and Bob

Gail and John Aiken look after the Northern Koanga Fruit Tree Collection which is planted at their home in the Hokianga. They are also seed growers for Koanga and Gail is the Back Order Manager. Over the next year they plan to hold a series of workshops and tours at their farm near Rawene. If you would like to be put on a mailing list for these events please e-mail [email protected] …..

We planted the first trees in our orchard here in the Hokianga in winter 2009 and this summer had  bumper crops of some varieties.  We are just loving having so much fruit.
The season began with Orion peaches – they were ripe from the second week in November and were a wonderful introduction to the bounty to come. They are so early in the season, they fill an important gap. They are smallish, white fleshed peaches and heavy croppers. We ate ours just as dessert peaches.
Next, were the Mary’s Christmas peaches. These are large, white fleshed peaches with outstanding flavour and very juicy. Here in the Far North ours were ripe mid December and lasted until just after the Summer Solstice.
We then had a run of plum varieties – small ,juicy, yellow fleshed Marabellas, large, red-skinned, red-fleshed, Little John’s which were incredibly sweet and delicious. Duffs Early Jewel and then Whakapirau Gold. All beautiful in their different ways and we ate them all as dessert plums as we’re not getting heavy enough crops yet to start bottling and preserving.

jim armstrongJim Armstrong Black

In late January the peaches really began again. We have a tree that we’ve called Jim Armstrong Black which seems to be a variant on the River Peach. It’s strong, healthy and a precocious cropper. Last year we had a large crop but this year its huge (over 600 peaches on one tree!). Its ripening time overlaps with the River and the Christina so we had huge bottling sessions, preserving them for later in the year. It’s been fantastic being able to have fresh peaches as snacks or simply with cream or, even better, kefired or cultured cream. We have peach smoothy for breakfast most days and have been making peach crumble (with an almond topping).
I invested in an ice cream maker so we’ve been making peach and vanilla frozen yoghurt which is really simple to make. We use most of our cream to make butter but always have heaps of yoghurt so it works better for us to make frozen yoghurt rather than ice cream. We blend up a banana, heaps of peaches, a generous table spoon of honey, two egg yolks, a litre of yoghurt, some spare cream, if we have it, and a dash of vanilla. Once its blended we just set up the ice cream maker, pour it in and away we go.
Yesterday, we had the best dessert yet. We made a fruit salad with heaps of peaches, Goldmine Nectarines (also ripe at present and cropping very heavily), Poutu blackberries, wild blackberries, some Whakapirau Gold plums, Early Tioga Strawberries and Red and White Alpine Strawberries. We drizzled some of the juice left over from bottling peaches on top and served it with the peach frozen yoghurt and some kefired cream! It was divine.

arapahoe 3 for e-mailArapahoe Red Leaved Peach

Next was the Arapahoe Red Leaved Peach. This is a stunning tree with deep red leaves – ours is planted in a prominent position on the way into our orchard and usually attracts positive comments from people who see it. That gave us a huge crop of red skinned, yellow fleshed peaches with a very intense flavour (my favourite I think although its a hard call).
Our Hokianga Golden Queen is small yet but gave reasonable crop and we had heaps of Matakohe Peacherines.
There are so many advantages to planting varieties that ripen at different times. Just being able to eat fresh peaches from November (the Orion) through to late March / early April (the Batley) is the most obvious advantage and also the preserving can be spread out over time too so that it is manageable. It also spreads the risk if the weather turns bad so even if you loose one crop you shouldn’t loose them all. Brown rot is the big issue up here in the humid Far North and we have been blown away by how resilient the Jim Armstrong Black, Arapahoe, River, and Christina have been. We’ve had appalling weather for peaches (hot, humid, sticky) just as the heavy crops were ripening but have lost very little. We tried to site all of our peaches well so that they have what air movement there is but we were concerned we might loose them anyway as the weather was so awful but so far we haven’t had any significant problems.
Next were the grapes – so many Bishop Pompalier and Niagara that we had heaps to eat, made juice with our steam juicer and made wine with them.

Giant Geniton 2 for e-mailGiant Geniton

Apples were next. The big surprise this year was an apple we were trialling called Jacqui Sharp. Nice as a dessert apple but a fantastic cooker. Lovely flavour and cooked down to a soft, sweet, fluffy puree. We also tried baking them at they were excellent – soft and fluffy within the skin.
Our apple crops were not large from such young trees but enough to try some of the varieties – we baked some Sturmer – delicious, had Winesap as dessert apples but also tried baking them and they were lovely. The Hayward Wright looked stunning and are lovely dessert apples.

Wrights Scarlet Crab 3 for e-mailWright’s Scarlett Crab-apple

We had huge crops on all of the crab apples – Golden Hornett, Wrights Scarlet and Jack Humm. They looked beautiful. Our biggest cropper so far is Giant Geniton – good as a cooker early in the season and as an eater later and always a precocious cropper so you get good crops from young trees.
Now (in April) we’re seriously into figs. Beautiful sweet black skinned, pink fleshed black figs, stunning Adriatic with its green skin and the surprise of bright scarlet flesh inside.  Small sweet hyndemans, and long amber Kaeo. All beautiful in their different ways.

Gail and John's property in the Hokianga
Gail and John’s property in the Hokianga
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Appropriate Technology – Ram pumps for low head applications


About the author Tim Barker

Tim has come a long way since his days as a diesel fitter mechanic and now spends his time between Australia and New Zealand as a semi professional pyromaniac and mad scientist teaching people how to burns stuff and make really cool machines and devices for low carbon living. He currently teaches Appropriate technology for the Koanga institute in New Zealand and Eternity Springs farm in Australia.  His rocket stove and char making powered hot water systems, ovens and cookers reflect his passion for elegant simple and durable combustion technologies, other projects include gravity powered water pumps, solar thermal cookers and dryers , Pedal powered washing machines, cargo bikes, hovercraft, wooden boats and aquaponics. Upcoming courses that Tim will be teaching are  a rocket hot water system and  oven workshop for VEG (very edible gardens) in Melbourne on the 26-27 April at Darren Doherty’s farm. A PDC for the Living in peace project in Karamea on the south Island in New Zealand from the 5th-19th May and  another PDC and appropriate technology workshop at Eternity Springs farm 17-30th of August. Early next year he will also be delivering his usual hands on appropriate technology workshop and internship for his home away from home in NZ the Koanga Institute.

People are always fascinated by ram pumps. I think partly because they achieve the seemingly impossible task of pumping water to a higher height than the water supplying the pump and they do it for no added energy input. This is often misunderstood as needing no energy but even a casual understanding of the laws of thermodynamics tells us this is impossible. You will notice I said no added energy input because fundamentally what a ram pump does is harvest the energy of a lot of water flowing through the pump from a low head source, to pump a much smaller volume of water to a higher head. Head being the height of the water relative to the pump.


Imagine if you will a pipe with an internal diameter of 100mm with water flowing through it. If the pipe is around 25m long then the weight of the water in the pipe is close to 200kg remembering that one liter of water weighs 1kg. This is basically one of those large oil drums full of water.

EmGv66Water is basically incompressible, meaning that you can’t fit more water into a container by cramming it in under pressure than you can just by pouring it in. So lets imagine 200L of water in an oil drum free falling under the influence of gravity. Next, lets imagine it hitting a concrete floor. For one thing the stop would be sudden and the force and the noise would be great. This is exactly what a ram pump does, the water falls through the pump gaining velocity until that velocity is sufficient to flip the waste valve shut. Suddenly you have a lot of water, which was an instant before travelling at quite a speed, stopping instantly. As you can imagine with nowhere to go (like the concrete floor in our example) we have a lot of energy to dissipate.

By putting a one way vale in a much smaller line coming off the main pipe we can use the energy in the main flow of water like a battering ram to punch the water past the one way valve and up the smaller pipe.

The energy of the sudden stop starts to dissipate as more water is pushed up the small pipe. Eventually the energy is exhausted, the water flow stops and at this point the one way valve shuts, trapping water in the smaller supply pipe waiting for the next hammer blow of our watery battering ram. At this point the water in the main (drive pipe) is totally stopped and even starts to “bounce” back just a little from the shock wave of the initial “hit”.

It is this reversal of flow which creates a small negative pressure in the pump that allows the waste or Clack valve to drop open via gravity and start the process all over again.Now I want to go back to the point in the cycle where the water is pushing past the one way valve and go into a little more detail, as I have, for the sake of clarity, left out a vital component of the system.

Attached to the outlet side of the one way valve and branching off the delivery line we have a tank with air trapped in it. This tank’s job is to act as a shock absorber and smooth out the pressure spike of the ram. Without this tank the pressure spike can be so great it will impact on the service life of the pump. After the one way valve is shut the pressurized air in the tank re-expands and continues to push water up the delivery pipe greatly increasing the efficiency of the pump. Those tempted to do without the air tank be warned. Just to see what would happen  ran a 100mm diameter ram with only 1m fall and a lift of 3m and managed to tear a 50mm check valve to bits. Now the valve was a good quality glass reinforced plastic one rated to over 100psi. While I should have been mortified at the destruction of the valve, I couldn’t help but feel an evil glee at the clear demonstration of the forces involved.

This short animation on Youtube will help make things a little clearer.

If ram pumps have a downside, the one that most often comes to mind is the need for a certain amount of fall under which they wont operate. Depending on size and other factors minimum fall is between 500mm and 1000mm. We also need to realize that when it comes to energy there ain’t no such thing as a free lunch, so how much fall we have directly effects how high we can pump. Typically most commercial rams are quoted as being capable of lifting water ten times the fall so 1m of fall will give you 10m of lift. It also stands to reason that the higher we pump the less we will pump as we are having to use more energy simply overcoming the  greater weight of water in the delivery pipe.

Recently I was presented with a challenging site where the creek the client wanted to pump from had a maximum fall of 1m and the height we needed to lift the water simply to get out of the creek gully was 20m. From the numbers given earlier, the upper range we could hope to pump to with a 1m fall is 10m so it usually wouldn’t have been deemed possible. Add in the factor that I was hoping to build the ram pump myself and that performance figures for other homemade rams were generally given to be  in the region of 5m lift per metre of fall and the task looked all but impossible. The icing on the cake was that the creek was prone to flash flooding and to get any fall at all the pump would have to sit directly in the creek bed right in the way of logs and such when it flooded.

It didn’t look good till I hit on the idea of staging two pumps to get us up and out of the gully.

The idea goes something like this, first we use our low fall (1m) to run a large ram pump and pump to a low delivery head (5m) and then let it fall through a smaller ram pump from the height of 5m back to the creek. This effectively gives us a small pump running with a fall of 5m, which even on the lower end of the drive to head ratio (5:1) gives us enough to get up and out of the gully

Luckily I even had a small pump I had built previously and tested, that I knew would do the job with the given fall. Perfect.

All that had to be done then, was work out the volume of water required to run the small pump and then build a bigger pump to supply that volume with a little spare capacity. After a lot of research and some mid range number crunching (not one of my strengths) I came up with a pumped sized to use a 100mm drive pipe. My target was 40 liters a minute delivered to 5m above the creek.


In the photo above you can see the pump design I came up with. Ram pump size designation normally comes from the diameter of the drive pipe in this case 100mm. Going from left to right we can see where the 100mm drive pipe attaches then the main body of the pump (big steel box) and then the waste valve (square opening) on the right.

An important design consideration is that we want the water to gain the greatest velocity we can as, the faster the water, the more energy. This is especially important when we have very low falls as we have less energy to start with so an important consideration is a straight flow path from the drive pipe inlet to the waste valve outlet. 90 degree turns and such will rob energy. Also we want the waste valve outlet to be at least as big as the pump inlet (remember we want maximum flow for maximum energy). To do this I worked out the cross sectional surface area of a 100mm pipe(78.5cm2) and then cut the waste valve hole to be slightly bigger 100mm x 100mm (100cm2). I did this before actually getting the pipe and because we were using scrap when it turned up it was actually 112mm internal diameter which is 113cm2 cross sectional surface area. Unable to resist getting the absolute best out of the pump I remade the waste valve and opening larger, so that once again it was larger than the inlet, so no flow restriction.

Again under the theme of getting the most energy, a waste valve that shuts early won’t allow the water to gain the greatest velocity, and as we already know, we have limited energy to start with, so anything that interferes with that is a big no-no. To that end we need a waste valve we can tune so that it closes just as the water is gaining it’s maximum velocity.  Anything less is wasted energy.


It’s a bit hard to see in the photo, but our waste valve is a heavy steel flap hinged at the bottom so it lays back into the oncoming flow of water. You can see the row of four small shiny bolts in the square waste valve opening -these attach the valve plate to a stainless steel door hinge. The valve drops open under gravity because the plate it is bolted onto is angled back. The adjusting bolt simply passes through the center of the valve plate(single big bolt in the square opening) and can be adjusted so the angle the water passes over the valve plate can be adjusted. We’ve all stuck our hands out a car window and made those wavelike motions up and down and you will have noticed its easy to keep you hand horizontal to the air flow but the instant you angle up or down a larger force flips you hand up or down rapidly, this is exactly what happens with our valve.

Of equal importance to all I’ve written about so far is the need to use rigid materials for the drive pipe and the pump body. The reason these pumps work at all is to a large degree due to the incompressibility of water. So imagine our 200L liter barrel falling towards the floor except this time its a large tractor tube filled with water. For a start we will get more of a splat than a crash, and there wont be any chipped concrete, that’s for sure, and that’s because the energy of the falling water is, to a great degree, dissipated by the elasticity of the rubber tube. So it is with our drive pipe and pump body. If we make them out of materials that have some “give” in them, then we are wasting energy by flexing those materials. You will see lots of ram pumps on the internet using plastic parts for the drive pipe and the pump bodies and these certainly work well if we are in a situation where we have enough energy that we can waste a fair bit of it . Ultimately however, if we are talking maximum efficiency, then rigid materials like steel are best. In the end it comes down to what you need and what it costs. For us we needed steel because of our low head and also for durability as this thing will, over the course of its life, have whole trees coming down stream and smashing into it, so plastic pipe just doesn’t cut it.

Most of the designs you will see on the internet tend not to be designed to sit right in the stream bed and certainly most aren’t designed to have logs and boulders crashing into them. They tend to have air tanks that stick straight up from the pump-body so they can trap air in the top of the chamber to act as a shock absorber, generally with a device called a snifter valve that lets a tiny gulp of air into the chamber each time the pump cycles. This is so air under pressure isn’t gradually dissolved into the water in the pump (just like CO2 into a bottle of soft drink) . This would then make the pump act like it had no air chamber with the result of lower performance and far greater stress on the pump parts.  Anyway, as you can imagine, in a flood, air chambers that stick up will tend to get damaged far more easily than ones that lie flat -so we designed ours to lie flat. This required that instead of a snifter valve, we trap air in the chamber using a different method, because for one: a snifter valve doesn’t work well with a low air chamber. Secondly, our pump is sitting right at water level so the minute the water level rises and the snifter valve goes under, the air chamber will fill with water and the pump stop. We got around this simply by filling a car tube with air and stuffing it in our air chamber so the air was trapped in the car tube and couldn’t dissolve away with the result that the pump will continue to run under water as long as we still have sufficient fall.


The air tank in the photo is salvaged from an old LPG vehicle tank, and before you ask, the fitting on top of the tank is just the original from when it was in a car and is retained purely to seal the tank. You can also see water starting to build up velocity as it exits the waste valve.Another important factor in getting the most out of a ram pump is the length of the drive pipe -too short and you don’t get enough mass going . Think of it like this: you have two battering rams, one is a power pole and the other is a pool cue. Both are made out of wood but we know which one will bash down a door. So you need the biggest reasonable mass of water you can. I say reasonable because over a certain length and you will actually start to lose performance again. It’s a Goldilocks thing, not too big, not too small, but just right. This has to do with the interactions of the various shock waves travelling up and down the pipe and certainly is not something I’m going to go into great detail. Luckily we have a rule of thumb calculation we can use to come to the correct lengths. Take the internal diameter of the drive pipe and multiply it by 150 and that will give you your minimum length. Next take the internal diameter of the pipe and this time multiply it by 1000 which gives you your maximum length. Now, if you have a longer drive pipe run because of site conditions don’t fret.  You put a stand pipe which is simply a pipe coming vertically off the drive pipe. If we do this towards the effective maximum length of the drive pipe as you’ve calculated it, then this will allow the pressure waves to dissipate and the pump retain its maximum efficiency.

Lets recap regarding factors effecting efficiency

Fall. Get the maximum fall of water into the pump, at 1m we’re right at the bottom of what is considered viable. In fact for 100mm ram pumps, generally 1.5m is considered the minimum viable fall.

Rigidity. The pump body is vastly overbuilt because the scrap steel we had was very thick (12mm) so is very rigid. However, other factors can effect rigidity. Any leaks in the drive pipe and the material the drive pipe is made of . Here we had some issues. Firstly the gasket material for fitting between our lengths of drive pipe was salvaged conveyer belt and was too hard and didn’t seal properly. Also after our initial run the pressure spike in the drive pipe found some internal weak points where the pipe must have been nearly rusted through. every time the waste vale shut we had water from various leaks shooting skyward. We have better gasket material ready for instillation and our local scrap guy has his eye out for some replacement pipe.

Tuning. We have adjusted the long bolt so the water builds to nearly maximum velocity before shutting. A simple test is to observe how far the water is gushing out the waste vale with the valve held fully open with a stick, this is our maximum velocity. Next observe how far the water gushes out when the pumps running. If its substantially less than when the waste valve is held open then adjust till it’s nearly as much. Too much though and it won’t shut reliably. A word of caution, don’t hold the waste valve open with you finger, here we can go back to my original analogy and imagine what would happen if your finger was caught between a falling  200kg drum of water and a concrete floor. Ouch!

Drive pipe length. Here we’re actually under our minimum length and as already mentioned the pipe is leaking so definitely sub optimal. Waiting on our scrap guy!

Pressure/Air tank. Here we’re good. Best practice is to size the tank to 50 times the pumped volume of one cycle of the pump, which, for this size pump, is around one litre. The tank is about 60L, so all good.

I suppose the next question is how did it go, considering our target of 40LPM and a few suboptimal factors.

As I stated at the start, due to boyish enthusiasm we fired it up prior to finishing the air tank and destroyed the check valve, so we knew we had harnessed some substantial energy. Or should I say we hadn’t harnessed it, hence the rupture. Once the air tank was finished and installed we primed the pump and started it up. A flow test at 5 meters gave us 36LPM. Considering the performance tweaks we know we have to address we will easily hit our target of 40LPM. Happy is not the word. We were stoked!


Next we installed a pressure gauge in the delivery line to see what our maximum delivery pressure was. We topped out at over 70 PSI ( sorry for the imperial measurement but I’m a PSI kind of guy).

This gives us a maximum theoretical pumping height of 49 meters. This means we could actually get up and out of the gully in one lift. Before you get too excited though, it is still to be assessed wether we could match the flow rate of the second stage pump to get the ultimate flow rate we required without the staging. But if its over 4LPM we’re in business!

It was about this time that a loud whooshing sound was heard and the Air tank took off down the creek spraying a jet of water out the back. We had salvage the old damaged valve and put it back together and under the strain of the pressure test it finally gave up it’s life for the greater good. A quick trip to town and a nice new brass valve was soon installed.


This shot shows removing the gauge after the pressure test. The water was shooting at least 15m vertically.

Considering all the adverse factors here, some of which we will shortly correct, I think it’s fair to say that the pump construction and instillation is and will be a resounding success and a vital part of the property’s infrastructure.

On my next post I want to explore some intriguing possibilities for ram pumps. Hint. What set of circumstances would allow you to take water out of a creek or stream and yet increase the volume of water flowing in the creek?

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Preserving traditions

Mulberry BlackThe end of summer/beginning of autumn is still a time of great abundance in the garden and in the local environment. We’ve been drowning in organic heritage tomatoes from our garden and further-a-field wild blackberries, walnuts and apples drip from the trees. There are way more fruit and vegetables than we can eat… One option is to just leave the food in the garden and pick as needed. Carrots and beetroots will happily sit in our raised garden beds all winter, particularly in colder areas.
However, as we are mostly self-sufficient and rely on the garden to feed ourselves, it makes more sense to pull the veggies out, store them, and start planting new crops.
All of which means: it’s preserving time in the kitchen.

The techniques we use for storing and preserving food were all once common knowledge, but these days tend to have fallen off the edge a bit. Just as with many permaculture ideas, rather than re-inventing the wheel, we are re-remembering the methods which served our ancestors so well.

DSCF2908The clamp is one of the simplest ways of storing root crops over the winter, you can build a frame, create a space in the cellar or simply cover your vegetables in a mound of sand.

When storing food in a sustainable, permaculture system, you need to think about using appropriate technology and the energy inputs and outputs of the process. Ideally food storage should be achieved with free, locally sourced, low energy materials, such as solar power instead of electricity to dry food, salting instead of cooking to preserve, stevia instead of sugar for sweetening and gourds, traditional Maori poha (bull kelp) bags, animal skins or citrus for storing, rather than imported agee jars.
You can read Marco’s blog on building a simple solar dryer here.
drid toms

However, before food storage even begins, we need to take things right back to the start and focus on remineralising the soil.  The higher the mineral content of the soil, the more nutrient dense and high brix the fruit and vegetables will be, and the better they will keep. Produce with a high mineral content will store for a long time, slowly wizening, while low nutrient produce will just rot. Getting the soil balance right is the basis of all our work at Koanga.

DSCF2912One of the more delicious preserving techniques is making food into pesto or chermoula, which can keep in a sealed container for over a year.

You can make pesto and chermoula out of practically anything, but here is one of the recipes we made on our latest food traditional food processing and storing weekend workshop:

Pumpkin seed and Lambs quarters pesto



½ cup Austrian hulless pumpkin seeds
2 cups Lambs quarters leaves
2 cloves of garlic
½ cup of olive oil
¼ cup solar-dried tomatoes
salt to taste


We used our wonderful Austrian hulless pumpkin which takes all the hard work out of dehulling your pumpkin seeds as they have no outer casing and ready to go as soon as you crack open your pumpkin.  This variety should be going into our July catelogue for you to plant your own. Lambs quarters is an easy-grow leafy green plant. We usually pick it a day prior to pesto-making day, so the leaves wilt slightly. This reduces the water content, which helps it to preserve for longer. Adding more garlic, chilli, lemon, oil and salt will further extend the shelf-life of your pesto. Cheese is also a tasty addition. We usually make pesto in vast quantities, but this recipe should make one small jar/orange peel container/gourd or whatever your vessel of choice is.


Simply grind up all your ingredients in a mortar and pestle or food processor and when you are happy with the taste and consistency, spoon into jars, leaving just enough room to pour a layer of oil over the top to help prevent oxygen getting in.

We’ll cover more recipes and preserving and fermenting tips in the next blog. In the meantime: Happy preserving.


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Joshua’s garden apprenticeship


I had, had a strong interest in permaculture and been gardening organically for a number of years in Auckland; as well as expanding my collection of psychoactive cacti & ethnobotanical plants (of which I plan to open a nursery for in the future).
Before I had learned the concepts of ‘nutrient dense food’ or even heard of bio-intensive gardening I had the intuitive feeling this would be my calling. I felt it would be of the utmost importance to learn how to grow food to provide nutrition for my future family & community in a sustainable way. When I learned of the Koanga Institute I immediately applied for the apprenticeship to seek  an opportunity to learn these skills.
I began my apprenticeship over five months ago in December. I have spent the summer honing my skills ias a bio-intensive gardener, thinking about permaculture principles & learning great life lessons about how to co-exist within a community. I love the experiences of community living & kinship here at Koanga. The people drawn to this crucial work  of saving organic heritage seeds are lovingly generous people. I have learned more about life during mealtime conversations than I ever would have having pursued a conventional education.

josh millie
Kay is a wonderful & dedicated gardener with a vast knowledge of Heirloom plants. While the teaching style here is much more hands on and less formalised than I am used to, I have still gleaned a lot of information from Kay. The very labour-intensive work is tiring and I often wonder if people buying our organic heritage seeds realise just how much energy goes into creating each packet we send out to them. However, I am enjoying the work as I feel the cause of the institute – to protect the Heirloom seed lines – is crucial.
As my garden goes into winter vegetables & compost crops I am feeling much more connected to the garden. Before I had ‘inherited’ many of the plants, but now I am raising them from seeds. I am looking forward to the winter season where I hope to carry out more of my own research.