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If you can garden in beach sand you can garden anywhere.

After three and a half years of seriously collecting mulch materials I suspect that I now have the beginnings of a garden.

This change has kicked in because I now have dirt where once sand ruled. 

At some time over the past 6-8 months this qualitative  metamorphosis kicked in. Now, at the end of a very dry Summer -- when we are still officially in  drought -- I can dig  my fingers into the dirt and grasp a rich loam.

And I got critters ++++ in my dirt. Worms especially -- when once upon a time there were none known to roam. 

I think  worm activity rules the quality of the underfoot establishment and I guess I can now call myself a vermiculturist.

Feeding my soil takes a lot of effort. How many times have I carted lawn clippings from my front nature strip to the outback patches? Layer upon layer -- a recipe  enriched by collected newspapers and manures, a bit of blood and bone, twigs and sweat. 

Constantly spreading the green stuff, hunting down any more carbon materials I could get my hands on, fretting over soil quality and irrigation options.

So I guess it took me 3 years to graduate.  

The disconcerting thing is that having spent so much of my energy focusing on creating soil from sand I only now begin to address the question of growing plants better in it.  Maybe now I can begin to look at pH  issues and some of the other horticultural parameters that make for  good cropping. 

But what a great adventure it has been.  (Read about it here. If you can garden in beach sand you can garden anywhere.

En route I have to say that the gardening literature was not all that helpful. So much of what I've done has been trial and error. Most of it presumes that you start with dirt and not sterile granules devoid of an active biology. And the irrigation handbooks simply have no concept of how porous my untreated sand is...still is. 

Now my garden is 'perched' atop of sand like a Fraser Island lake. The difference is that my 'garden' isn't impermeable. It just slows down the water as it diffuses through the soil long enough to foster the makings of a garden. I suspect that without the addition of clay  it will remain very permeable. So my interest is in seeing how much I can do in way of soil improvement with organic matter alone. My working hypothesis is that big bits of organic matter -- my favorite being rolled up newspapers -- act like sponges, holding onto more moisture than the surrounding soil. 

This is my number one principle -- a principle that underlies my use of clay pot irrigation. Indeed, I guess I  have added clay to my soil -- but in the form of  buried flower pots.

Sometime this year I'll write up my experience in as a sort of DIY manual for those who may be interested in  a few hints for gardening on sand.

But outside of all that I gotta say that my main inspiration--aside from local Wallum ecology --  has been the rain harvesting work of Brad Lancaster and the literature on vermiculture, especially David Murphy's wonderful book , Organic Growing With Worms.  As the irrepressible Peter Cundall writes in regard to it:

"This is an amazing, inspiring book..it should be on the bookshelf of every farmer, gardener, conservationist, scientist or anyone who comprehends the environmental dangers now threatening all life forms on earth."

 

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Comment by Dave Riley on March 25, 2014 at 13:47

I think I've well and truly shocked myself.

I was outback today inserting in a few more honeyholes -- and I was amazed by the extent of my vermiculture activity below the surface.

After hardly ever coming upon a garden worm I'm now over run with big fat juicy wriggly things.

Previously I'd mulched thick and sheet fertilizered with manures...and most of what I was doing was fostering breakdown so I'd get loam out of sand. But as soon as I embedded my terracotta pots as a secure water resource AND started trench mulching in honeyhole mode, the soil biota has changed sharply.

In effect I have introduced watering and feeding stations to selected locations in the garden beds. And the mix seems to work: Plenty of paper/cardboard soaked in water in a wheel barrow > torn up  then mixed with manure and grass clippings >churned up and marinated  for a couple of days then used as fill in shallow vertical trenches no more that a forearm deep. 

I don't have to turn over the whole bed, nor disturb roots if I stick to isolated patches. Nor do I have to start a new bed or wait out some composting process...And it is very efficient use of limited materials in the way that Lasagna gardening (see picture)may not be. 

It presumes that you have 'staff' working for you spreading the good stuff, ferrying it about and converting it into loam. Working in the engine room so to speak.

I assume that because I am on sand,  getting about for critters is gonna be very easy as the pathways are easily made... They're like a shopping town malls. 

I'm imagining a sort of commute between feed and watering stations.

Vertical/trench mulching is deployed a lot in US tree maintenance but I've found very little about it aside from Brad Lancaster and the honeyhole story....and traditional vermiculture (esp as per David Murphy).

Comment by Andrew Cumberland on March 24, 2014 at 19:22

Soil is the pantry of my plants.  If I let it run out of food, then nobody eats.  That simple. 

Comment by Elaine de Saxe on March 23, 2014 at 22:04

Because still, so many people believe or act as though soil was just 'dirt' and sterile. If they understood the delicate and powerful web of health and prosperity that real living soil is, they would never bombard it with the crap they have been putting in and on it for decades.

Comment by Dave Riley on March 23, 2014 at 21:52

Not directly related but very much the BIG picture: Why is soil missing from the 'big five' environmental questions of ...

Just published by ABC Rural. 

Comment by Jane on March 23, 2014 at 12:29

Thank you Dave for posting this also Elaine for your comments. I recently brought red compost worms for the first time - in 30 years of gardening, just never bothered with them but will now also add some to my cooling & maturing compost. Last year I notcied very few garden worms, realised I had let the humas content drop, now after collecting & adding lots of flood litter & compost & mulch the worms are back. Contary to your sand Dave i have a thin layer of soil over clay which goes all clogy if the humas is allowed to drop, have never worked with a sandy soil it seems a lot more work to me so well done.

Comment by Dave Riley on March 23, 2014 at 8:07

When you consider it the way that earth worms have occupied the world -- piggy backing colonisation and other human invasions -- makes them pretty marvellous. Generally we're talking about a benign and productive local impact although I see where in some North American temperate zones they have changed soil ecology to the detriment of indigenous  flora and biology. 

In Australia I assume that the worms we garden with do tend to be restricted to 'gardens', orchards and  farms where human efforts have radically changed the soil. But then I guess that even in the bush the exotics have found a niche.

"Australia has 650 known species of native earthworm that survive in both rich and in nutrient-poor conditions where they may be sensitive to changes in the environment. Introduced species are commonly found in agricultural environments along with persistent natives. Most of the 75 or so exotics have been introduced accidentally. The total species numbers are predicted to exceed 2,000."

Comment by Elaine de Saxe on March 22, 2014 at 21:10

Interesting, great detail. It's that sort of information that makes sense of having earthworms in the soil.

I don't doubt that red compost worms are tough critters. Some years ago I brought home some commercial worm castings. In those castings I am assuming were juvenile red compost worms and/or the egg capsules. By some means I'm not clear on, enough worms escaped from the bags of castings which I stored next to my compost bins.

The compost bins are made from plastic garbage bins with some holes in the bottom - just small holes for drainage. The worms must have realised there was food available and have taken up residence under each of the 5 compost bins. When the raw kitchen scraps with some carbon material and BD 500 reach a stage suitable, the red compost worms come into the bins and begin chomping.

They are still living under the bins - saw them today when I put down another batch of compost. Each time I use my compost when I put in some new plants, I transfer some of the worms too.

I rarely dig around once the plants are growing but now and then I peep to see if there's worms still in the garden. In most places there are, so given the right conditions, red compost worms survive in garden beds.

Comment by Dave Riley on March 22, 2014 at 18:22

Yes that's the complications with compost worms -- do they survive when they camp out? Of course if you have a regular supply you can seed the garden spots and let them eat their way with what's on hand until it runs out and in dying the worm services you still..

Not that worms have hands but a wiggle more or less is a menu change.

Since 'our' local garden worm  is a foreign import --a Peregrine earthworm -- how it works in the soils we foster is surely a fascinating topic. While the compost worms do seriously change stuff into compost what do the everyday garden variety do?

Useful overview: (NSW Dept of Agriculture) How earthworms can help your soil...but David Murphy's books are awesome.However much research is in  temperate zones.   There are supposedly  36 exotic worm species in Queensland soils.

But also, this snippet: TREE FRUIT: Earthworms- natures soil improvers:

Chemical effects
Earthworms are omnivorous, so their food includes fresh and decaying plant and animal matter and soil.

The nutrients from the food are extracted for the worm’s use and the balance is excreted as casts. But it is how worms affect the soil they eat and live in, that is important to orchardists and gardeners.  

A skin excretion of slime, to assist in the worm’s movement, and casts are responsible for some of the nitrogen in the soil. But most of the nitrogen comes from earthworms when they die.

Depending on the worm population density, earthworm carcasses can release 18 to 90 kilograms of nitrogen per hectare annually.
With a nitrogen to phosphorus to sulphur ratio of 12:1:1, dead worms would also contribute a further 2 to 9 kilograms per hectare of phosphorus and sulphur annually.

As earthworms burrow and feed through the soil, they set free bound-up substances, like phosphates, by breaking down the large complex molecules into more simple plant-available forms.

When the chemical analysis of the excreted material is compared with the surrounding soil, castings contain five times more nitrate, seven times more phosphorus, three time more exchangeable magnesium, one and a half times more calcium, and eleven times more potassium than the surrounding soil.

Castings also have a neutral pH and have a higher base exchange capacity (ability to react with nutrients) than the surrounding soil.

But the casting content is dependent on the organic matter and mineral content of the soil that the worms ingest. Worms cannot make something out of nothing.

Since earthworms produce their body weight in casts every 24 hours, a well worm-populated orchard or pasture, can turn over 70 tonnes of soil per hectare between spring and autumn.

They can consume the leaf litter from an orchard in autumn in three months. In doing so, they can have a significant phytopathological effect on some harmful fungi, such as black spot (scab) of apple and pear.

This fungus overwinters in fallen apple and pear leaves on the orchard floor where fruiting bodies form. If the leaves are not consumed by earthworms and microflora, spores are dispersed from these fruiting bodies when temperature and humidity conditions are right for an infection period in spring. Young leaves and fruit on the trees are then infected.

It has also been observed that earthworms eat directly the fruiting bodies of the brown rot fungus formed on dead stone fruit prunings on the ground.

Physical effects
Earthworms improve soils physically by tunnelling through soil, by mixing organic litter into the soil and by producing casts.

They also improve nutrient cycling by mixing fertilisers with soil.

The microbial activity, either within the earthworm’s gut or in the casts, produces gums (possibly polysaccharides) or fungal hyphae, which stabilise the casts. Calcium may also be partly responsible, since calcium stimulates earthworm activity.

In temperate Australian soils, which generally have low amounts of surface litter and are dry through summer, earthworms are inactive throughout summer.

However, in a non-cultivated peach block at the Tatura Research Institute, where large amounts of organic matter have been added annually for 10 years, and the soil kept wet by irrigation, earthworms remained active throughout summer.

The entire surface soil (0–200 mm) appeared to be casts and probably had passed through earthworms many times.

Earthworms produce their own tunnels to live in and move around, as opposed to some animals which live in cavities formed by other animals or roots.

Soils, where earthworms are very active, have an extensive network of inter-connecting horizontal and vertical tunnels, generally continuous to the surface.

The earthworms exude mucus, which stabilises the walls. The soil lining the tunnels is not compressed, because earthworms ingest rather than push their way through soil.

They tend not to enter subsoils unless the subsoil is disturbed. This is probably due to poor aeration and lack of food.

The tunnels are stable and may persist for years after the earthworms have left. This may also be due to the oriented clay particles and concentration of humic materials, iron and calcium, which have been shown to line the tunnels.

These stable inter-connecting tunnels are important for movement of water, air and growth of roots.

The tunnels, which are 1 to 10 mm wide, depending on the size of the earthworm, increase the macro-porosity of the soil.

The tunnels increase water infiltration, drainage and aeration. For example, at the Tatura Research Institute, an irrigated peach block with an ample supply of food and water, had 2000 earthworms per square metre of topsoil, compared with 150 worms per square metre in local orchards without ample food and water.

In the same research block of peach trees, the water infiltration was 80 times, and the macro-porosity four times that of the local orchards.

We also found that roots used old earthworm tunnels and root channels (called biopores), and could penetrate harder soils with, than without tunnels and biopores.

Earthworms are also emerging as a highly efficient tool to remove pesticides and pollutants from soils and combat climate change by reducing greenhouse emissions from landfill waste.

Recent studies found that earthworms removed heavy metals, pesticides and organic micro-pollutants from soil, a technique known as vermire-mediation.

You may now realise how valuable these slippery, ground-dwelling creatures are.

Yes, the humble earthworm does not deserve to hang on a hook or be drowned.

 

Comment by Andrew Cumberland on March 21, 2014 at 22:43

I reckon slow and steady will always win the race.  Well done Dave. 

Comment by Elaine de Saxe on March 21, 2014 at 10:06

The native soil-worker worms are such great little people to have around! The red compost worms (just happens to be the ones I have) do a mighty job in their area too. They both do different but necessary jobs in our soils. And despite what I read in the past, the exotic red compost worms will live in good soil. Finally I have some living in my wicking beds - I put them there as you need to do with wicking bins since they're not in touch with the surrounding soil.

Earthworms of any kind eat the bacteria and fungi growing on the organic matter - not the organic matter itself. So if the worms are thriving they are eating (and procreating) and your soil whether natural or artificial, is doing what it need to do, to grow healthy plants.

Indeed a benchmark!

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