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Sunday, June 10, 2012

Wicking bed


Merri Bee Organic Farm  is creating a natural system of perennial abundance to satisfy human needs in food, shelter, energy , community and wilderness, whilst restoring a cleared and overgrazed piece of rural land. Our farm is designed as a ‘closed loop’ in which the yields and by-products of one system are used to satisfy the needs of another, constantly circulating nutrients and harvesting water and energy via multiple elements. We aim to protect soil biodiversity and its many ecological functions. We are exploring and demonstrating these principles, educating and inspiring people to perpetuate the building of sustainable infrastructure. An example of this is
wicking beds
  We set up a wicking bed in a hurry recently to demonstrate how little water it takes to grow veges in this set up The growth has been phenomenal.... lettuce seedlings of the same size were planted in an adjacent, well watered and composted garden. The garden has had to be watered ( with a butterfly sprinkler ) once a week , the wicking bed only once a month. The lettuce in the wicking bed are 3 times the size of the garden lettuce. We dug a 150 ml deep level pit, lined it with black plastic and laid a 90 ml old storm water pipe we found at the tip on that .
We had previously cut numerous slots in the pipe and positioned the slots downwards, so the pipe won’t fill up with dirt. We put a plastic bag and a rubber band over the end of the pipe. Conveniently the pipe from the tip came with a 90 degree bend  ( elbow ) attached. We inserted another length of pipe in it, and set that up vertically. That’s your water filling pipe. We  then surrounded the pipe with small rocks at one end and woodchips at the other.

The woodchips were much lighter and easier to work with . I will see which end works best for the longest time. So you now have the 150 ml pit filled with aggregate which creates big air spaces between chunks, which will often be full of water. The aggregate essentially holds up the soil above. Place a thick layer of leaves or grass clippings , or a sheet of shade cloth on top of the woodchips or rocks. Then fill the bed with good soil and compost mix to a 350 ml depth. It can be up to 400 deep but no more, as the water can only wick up to a height of 400 or so. 350 is deep enough for most root zones. A drainage hole is essential at the level of the shadecloth. Otherwise a down pour or forgotten hose running would result in waterlogged plants. Which will die. You then hose or bucket water into your plastic lined gravel or wood chip-filled reservoir , via the fill pipe  until  water starts emanating from the drainage hole . In the event of a down pour, this drainage pipe or hole will ensure the soil doesn’t become waterlogged. In our case, water just begins leaking out at ground level (where the plastic liner emerges)  when the reservoir is full. I like the fact I can go away and pick some parsley while the running hose fills the reservoir. If I get carried away birdwatching the excess water will only benefit plants down hill of the bed.
After all this work and materials, plant your seedlings and water them in as usual.
 Prepare to be amazed as they thrive without any further attention from you for at least a month. That’s what we found, and we certainly hadn't had much rain. See pics of the plants in the wicking bed just one month later, compared to the pale undersized lettuce in garden ( which had been watered with over head sprinkler every second day) My photography sucks, but I hope you can see the bigger and lusher growth in the wicking bed. Tried to deliver same amount of compost to both lots of plants also. I think the sprinkler watered lettuce bolted to seed soon after the picture was taken.
We want to experiment with  wicking beds as a grey water treatment system,  having trickled it first through a rock column then through a wicking bed planted with reeds  to remove nutrients . The reeds could be used for mulch. 
 A google search will reveal many different types of wicking beds and no doubt YOU will come up with great innovative ideas we would love to hear! My friend Tash Levy has successfully used bentonite clay instead of a plastic liner. We will be following her lead on our next one, as it is more natural and less toxic to manufacture and use than plastic. Thanks Tash!
 Update! EDMP plastic is safer than PVC. Pond liners of EDM or butyl rubber would be of the safest kind of plastic and possibly worth the extra expense. We will also incorporate a worm feeding station for disposal of vege scraps.



Every home in arid lands should have a wicking bed! 


Here is some further great info from Rob and Michelle Avis in Alberta Canada: http://www.energybulletin.net/stories/2011-05-31/bottom-diy-guide-wicking-beds
How Wicking Beds Work
A wick works through capillary action – the same force you observe when you dip a piece of tissue paper partially into a glass of water and watch the water climb the paper.  Wicking occurs in many materials; cotton, wool, geo-textile, soil, gravel and even wood to some degree. Every material has different wicking properties which you can test by placing that material into a glass of water and watching the water “climb” up. When one end of the wick is saturated and the other end is dry, it creates a moisture gradient, which drives the wick until the gradient no longer exists or you run out of water. With the earth box, one of the more popular examples in North America, the soil is suspended above the reservoir with wicks dangling into the reservoir pulling up moisture. As the plants use the moisture in the soil, it creates a moisture gradient (the soil is drier than the reservoir) which drives moisture through the wick into the soil.
Advantages of Wicking Beds
Wicking beds have a lot of advantages over standard raised beds and in-grown swale-based gardens:
·         They are water-efficient! Watering from the bottom up prevents evaporation of surface water (which occurs when you water beds from the top).
·         They are self-watering! Wicking beds are an especially great system to use in community gardens because they save people from driving every day during hot weeks to water their beds. A full wicking bed should irrigate itself for about a week.
·     
·         No evaporation means no salting of soil. If you are watering your soils from the top with slightly water, you risk accumulating salts, because the water evaporates and leaves the minerals behind. Eventually your soil will struggle to support plant life.
·         They provide a lot of drainage in the event of a large downpour.
·         Since they're raised, they will warm up quicker in the spring.
·         You can easily attach cold frames or shade sails or birdnets to them.
·         They are great for people with less mobility/flexibiity.
·         
Disadvantages of Wicking Beds 
·         Are few!    *They cost more in time and perhaps materials to create than ordinary garden beds .
                * You can forget to water them altogether !
   UPDATE 

Our first wicking bed is going well, devoted to strawberries now. Second one has had a major problem.. I HAVE TO FIND TIME TO EXCAVATE  a large amount of soil out and see what is going on, because the reservoir always has water in it, it isnt going anywhere, but the soil is dry. Somehow poplar roots from a nearby huge tree have also  invaded it ,without piercing the plastic obviously, maybe through the jarrah sleeper joints?  So it is all a mystery.
 I have done a small wicking bed  lined with clay, it is going very well . I think the reservoir need filling more often and certainly doesn’t hold water for more than half a day but I think that means I didn’t use solid enough clay. It has a certain amount of sand in it. I used bentonite (as in no name brand kitty litter) , dry, as a layer over the wet clay, to faciitate a light pounding of the clay "pond liner" . It stopped my pounder getting heavy with sticky wet clay.
 Even though it only holds water for a few hours it is long enough for the soil above to wick it up. And for some reason, it doesn’t dry out for a week in high summer. No doubt during the other 3 quarters of the year it will  barely  need water.  I did put quality aerobic compost in at a rate of about 50 %. The strawberrys in this mini wicking bed with glass viewing window are growing well.


C Could there be problems with anaerobic conditions in the bottom layer of soil near the water reservoir? The rules are that you look down the pipe every few days and check the water level. You should only water again when the pipe has been dry for 1 to 3 days. If people are experiencing problems with anaerobic conditions they may be over watering.  

In our non wetting soil, the major advantage to wicking beds is being able to drop the hose going full bore  into a big pipe and go off and do something else for 5 minutes while it fills. You know the water is going right where your intended plant recipients are, and they are  going to get every drop. It is not going to grow weeds, the water isnt germinating weeds. 
  Anything that save us water and time is worthwhile in my book.



U


Wednesday, June 6, 2012

Maarten Stapper's talk at Permaculture Convergence

I just adore Maarten Stapper and here he is in full flight. Tune in for a great rundown on the best methods of soil improvement currently known to science. Maarten was once married to woman who, like him, worked at the CSIRO.  But unlike him, she was into genetic engineering. She remains on  a great salary no doubt  whilst Martenn  was sacked for his anti GM views. I am glad he is out of that those relationships and is sharing his vast knowledge and passion for soil science and organic growing with us.
 Thank you  and bless you Maarten         .http://www.youtube.com/watch?v=RzEYLKhIJt8&feature=related

Sunday, June 3, 2012

Swales


Connect the dots: Signs of Global warming are being seen all over Earth
Sea level rise
•Drying....Lakes have disappeared. Wells and springs drying
Heat waves
Cold snaps
Floods
Tornadoes and cyclones
Fires…intensity & frequency
Snow seasons failing
Glacial melt

In the South West of Western Australia a drying climate is leading to noticeable lower productivity. The sun is more intense leading (in our garden at least) sunburn on harvested onions and garlic, berries, capsicums  etc. It is much hotter , dryer and more humid in the last 5 years. We've been here for nearly 29 years with our hands in the soil most days.
  Soil erosion occurs when grass cover is sparse and rain events are so spread out....soil is lost when isolated rain events or wind dislodges dry uncovered soil. Deserts are growing globally. 75 billions of tons of topsoil are lost from the arable lands of Earth annually. In many places the old people now live in arid zones with little vegetation , but remember trees and their fruits and nuts of the district.  However SWALES (  dead level ditches on contour ) slow and sink the water. They can green the  desert and we must install them over vast areas. They harvest rain and make a deep wet zone where trees can establish .
Swales    
For Erosion control, Water harvesting, tree establishment.
OF course Trees are vital to a safe climate in the following ways: 

.Carbon sequestration ….occurs when trees are actively growing .
Shade, shelter, windbreak…
Habitat and protection  for birds, insects, mammals   Such biodiversity is biological pest control. Plagues are reduced.
Trees  cycle water :    transpiring  moisture  during the day  and condensing moisture on their leaves at night. They also provide  organic particles which seed clouds to make rain. Belts of trees on ridges are responsible for orographic rain due to the "lift" of the clouds up over them.. And more. Forty percent of rainfall is due to forests. Clear the forest and rainfall will reduce by 40 %. This effect will be fairly immediate. Though it takes much longer to put trees back they will increase precipitation dramatically once established. Obviously we need to get tough survivors of the tree world in the ground without delay in the current climate emergency.
Mulch/litter/  collector.  
This soil cover= carbon rich humus
 formation=  for every 1 % rise in carbon
 level , a soil it will have 4 times more water-holding capacity!! 
Rehydration of  the landscape 
( fungi / root mass/above ground biomass, soil biota are all mostly water)
Permanent Springs  and Creeks flow once more
Productivity through cash crops  eg fruit /nuts/animal products (extra fodder) / timber sales 


If you live in an area with only a 600 mm a year average rain fall, that means on every square meter of earth,  600 litres of rain will fall in an average year. That is the equivalent of  3 of those blue 200 litre drums full of water for each meter square!!   But sadly hardly any of that water gets into the soil. As with irrigation , most water runs off to the sea.
In the wonderful words of Bill Mollison

" In most countries 80% of rainfall runs off or evaporates. Thus only 12% is available for agriculture or domestic needs. We must legislate for the construction of thousands of miles of swales on farms, as large contour ditches that fill in every heavy rain (more than 10mm/day). In 3 to 6 hours, such water soaks in, and is immune to evaporation or run off. This water , over years and centuries, feeds tree roots, springs and valley streams. Swales enable forests, and forests are both passive condenses of night air, and active cloud generators or rainfall. If we clear the ridges, 40% of orographic rain ceases. If we clear the plains, most condensation and clouds fail to form. Thus, swales precede forests. Forests precede precipitation."

This is the swale we dug in March 2010, after a few months. Even though 2010 had  a half average rainfall, the grass in the swale grew twice as high as surrounding grass. We have found trees we planted in  and on either side of the swale have grown very well with hardly any irrigation. The trees will soon contribute shade, transpiration, leaf litter, habitat and thus manure of birds, insects and mammals. . 
To install swales you have to mark out contour lines. Stew dug these  with a tractor, leaving a soft mound of earth on the contour line. The contour of the land is a line which joins all  points of equal height above sea level. Every point on the marked line of 100 m 


elevation  on a contour map is 100 m above mean sea level.        I.e. A swale is dead level .  Water is simply held in the swale till it infiltrates the soil. This may take half an hour or a few days depending on soil type. It has no choice but to  enter the soil . Photo at left is of 5 recently installed swales at Merri Bee Organic Farm.  During isolated rain events  55 tonnes of water  enter the landscape through these swales as opposed to running off  to the Blackwood river and escaping to the sea. Instead of flood and drought scenarios, swales and attendant vegetation mean year round water in the environment. This is how Mother Earth likes it. 



 Unlike a swale,  a DRAIN  directs water and causes it to flow ( into a dam for instance)because it  has a slight fall, usually 1 : 1000 ( eg. drops one meter of a distance of 1000 meters. ) You can see contour lines on Google maps .  Type in an address, then choose the terrain option when in map  (not  Satellite). Sometimes you have to zoom out or in to get terrain.
Here's the swales 6 months later in September. Fabulous growth which will be mown down and to make mulch around the tiny trees we have planted. Really Cool. Cows will graze the 18 meter strip of grass between  swales. An  electric wire will keep them off the trees. Will have to move them daily but the soil improvement and their happiness will be worth it. 

Into our 7 month without meaningful rain, and heatwaves from November on, and the swales aren't looking too bad.
Here is a list of stock fodder trees we have planted on swales : . So  acacias and tagasastes  are interspersed with the long term trees. Fodder species include tagasaste, bamboo, carob, oak, sheoak, comfrey, saltbush, honeysuckle, coprosma, willow, poplar, ash, mulberry, grape, fig, apple, stone fruit, ivy, kurrajongs ACACIA microbotrya ( Manna wattle) Mulga ( acacia Aneura) ACACIA saligna , Wilga (Geijera parviflora,) Belts of trees not only provide high quality browse but shade and shelter, salinity and erosion control, clean air and water in the landscape . Oh and timber trees might be handy in the future too.

 

4 minute explanation of Genetic Engineering . Share please!


Really great short clip that explains the GE issue very well. Plase share this link with everyone you know.  http://youtu.be/zcTNmCUMZ7c