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Composting and Worm Farming

Sun, 19/10/2008 - 18:25 — bart
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COMPOSTING

Composting is a key aspect of successful organic veggie gardening. It turns bulk organic materials back into a useable soil ingredient. In a forest, bird and animal manures mix with leaves and twigs on the 'micro organism rich' forest floor. Broken branches and dead creatures are broken down relatively quickly in such a rich living system. Applying compost to your soil is replicating this natural process.
 
Adding compost back into your garden is required for maintaining good nutrient levels in the soil, and it also improves the structure of the soil layer, increasing both drainage and moisture retention. Not to mention that composting makes the most of every scrap of left over 'waste' materials from your garden and kitchen.
 
COMPOST BINS and HEAPS
Before you begin making compost, you need to find a good spot and set up one or more compost bins. There are a few different options, such as a two or three bin system made from wooden planks (or if you can find some old pallets, nail 4 of them together in a square for a quick compost bin), a store bought black plastic bin, etc. or you can just make a compost heap and cover it with carpet, grass clippings etc.
 
THE MIX
It's all about ratios... 
CARBON/NITROGEN (BROWNS & GREENS)
One of the most important ratios to get right, the balance of carbon to nitrogen dictates whether your compost will turn into rich black earth, a stinky slimy mess, or just sit there looking at you. Basically carbon provides the bulk matter for humus (the good black stuff that we are aiming to make when we compost) and nitrogen provides the fuel for the bacteria and microorganisms that do all the work. Not enough nitrogen in the mix and no matter how long you leave your heap it will still be full of untouched dry material. Too much nitrogen on the other hand leaves your compost looking and smelling like something evil...
 
BROWNS - carbon rich, dry
Browns are those that you could burn if left to dry out, they also help air flow and drainage of moisture.
Always start with a double layer of coarse browns for aeration and always build it directly on the ground.
  • torn up newspaper/cardboard, unbleached and unglossy paper
  • egg cartons
  • tree prunings
  • dry leaves
  • bark, untreated sawdust
  • wood ash
  • twigs and sticks
  • straw
  • cotton and wool rags (must be 100% natural)
  • hair

GREENS - nitrogen rich
Greens are materials that go soggy and smell if there is too much of it in one place.

  • fresh grass clippings
  • garden weeds without seeds
  • Fruit and vegetable scraps
  • seaweed
  • tea leaves and bags
  • coffee grounds
  • animal manure (grass eaters only)

Don't include:

  • meat or fish
  • dairy products
  • fats
  • oils
  • anything toxic (e.g. sprayed weeds)
  • anything artificial like plastic or acrylic
  • invasive weeds like couch grass and convolvulus
  • weed seeds
  • dog and cat pooh
  • Coal ashes
Opinions differ on the exact ratios to use, but in general a larger amount of Carbon to Nitrogen (the C:N ratio), say 1:1 (half carbon half nitrogen materials) will make a richer, faster composting heap, whereas a higher ratio, say 5:1 (5 parts carbon to 1 part nitrogen) will produce a more bulked up, slower composting heap good for applying as a mulch.

When finished it will be 30% of its original volume and will resemble dark crumbly soil. To get the maximum benefit from compost as a source of plant nutrients it should be applied to the soil surface in the spring. Do not dig-in your compost. Apply it as a surface mulch at the rate of 1 bucketful per square metre. Spread it on top of the soil and lightly fork it into the top couple of centimetres.

Healthy soil = Healthy Food = Healthy People.

Its free. Its everywhere. Its poo...
One of the most potent and useful sources of raw organic matter and prime nutrients available to us is almost entirely ignored by our culture, in fact we go out of our way to make it into a toxic waste problem, mixing it with vast amounts of clean drinking water and industrial wastes, which requires intense treatment and drastic disposal methods. The current sewage system in Dunedin essentially results in the nutrients from our soils ending up far out at  sea, resulting in the need for them to be replaced using unsustainible, non-renewable resources such as phosphates.
But with thorough composting and some common sense and basic precautions we can turn this problem into a solution, a massive source of nutrients for our soils. We eat from the top of the food chain, high quality foods rich in all essential minerals, it stands to reason that our shit is some of the richest around, especially in cities where there aren't too many other large mammals... Don't waste it. Return it to the soil!  
For more info read THE HUMANURE HANDBOOK by Joseph Jenkins
WARNING! NEVER use uncomposted human waste on your gardens, composting effectively decontaminates poo and leaves it sweet for your soil and your veges.
 
Note: wash you hands after working with your compost. Keep it moist to prevent spores and dust problems.
 
COMPOSTING LINKS:
 

WORM FARMING

Starting a worm farm is easy- best to start in the warmer months.

Site the container near your kitchen on the east or west side of your house (not in full sun or full shade).

•Get a large open container with drainage like an old bath, kitchen sink (no plugs in) or rubbish bin with 10mm holes drilled in the bottom. Raise it on a base so you can collect the rich liquid manure that will come out into a tray or bucket.

•Add a 2-3 cm layer of gravel or sand for drainage on the bottom.

•A 2-3 cm layer of damp shredded newspaper, old compost or pile of leaves as a starting base (bedding)for your worms.

•Place a good handful of compost (tiger) worms* amongst the bedding. (Your old compost heap should have these under it. They are striped and also known as tiger worms. (The pink worms you find in your garden are not the ones you need). Ask a friend who gardens or has a worm farm- or buy them from a nursery.

•Cover with a piece of old carpet, sacking or circle of wood with holes to cover the container so it stays dark and moist.

Caring for your worm farm: Wait one week for your worms to settle in then you can feed them building up to 1-2kg of food scraps each week. Place them in one segment at a time rotating each week.
They especially love coffee grounds, raw food scraps, After 7 weeks the first place you feed them should be like soil- if not feed them a little less. Do not feed them citrus, dairy or meat products.
If you live in a cold area, for winter only, wrap the container in some insulation material e.g. old carpet, sacking. (Optimum temperature 15-25oC but can deal with smaller amounts of scraps at lower temperatures). If it starts to smell sour add a sprinkle of lime or dolomite.

You can harvest some wonderful rich worm compost by feeding them in one quarter of the container for two weeks then the other three quarters will be empty of worms and you can gently scoop it out. Always add some more bedding in the empty space left.

GOOD LUCK! Soon you’ll have thousands of little white baby worms which will grow into busy active workers making heaps of compost for you and only wanting food scraps for their efforts! After a few months you can give a handful of worms as gifts to your friends! (They will also need a copy of this)

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Comments

Sun, 25/01/2009 - 17:01 — Tomartyr

Useful disposal of invasive or unwanted weeds

Most advisory resources on compost making recommend non-inclusion of "nasty" weeds, e.g. docks, convolvulus, buttercup, dandelion etc. One way to make good use of these weeds, which, incidentally, are usually very rich in nutrients because of the deep taproots many of them have, is to dump them in a covered bucket of water for a few weeks, thus drowning them. Meanwhile they will ferment and the liquid can then be poured off and used in diluted form as a nutritious plant food. The remaining dead, slushy weeds can then safely be added to your compost.

Sun, 25/01/2009 - 18:43 — bart

Liquidising weeds

Hi tomartyr,

It is effective for some species of weeds to do this to. But others, such as couch grass, can thrive even submerged fully in water. For extra stubborn ones I like to leave them out in the sun, spread out on concrete until completely dried out. This can take several days. They can then be put into either water or onto the compost heap (although do not put weeds with seed heads onto compost heap). This is one of the great merits of using a bin full of water, is that makes seeds infertile.

With the 'weed tea' thing, it's important to remember that fermentation usually results in fairly acidic liquid. So maybe it's good for things like potatoes but if using on neutral to alkaline pH loving plants, it may be necessary to mix in a bit of lime or something before use.

Sun, 25/01/2009 - 23:15 — Tomartyr

Fermentation

That is interesting about the acid effect of fermentation, Bart. I didn't know that. Thank you.

Thu, 22/01/2009 - 21:55 — Charlotte Handley

animal manure on compost heap

 Hi I am new in your patch. You state that only grass eating animals' manure should go onto a compost heap but you are also  suggesting that humanure is a very valuable resource - what happens if we are not grass eating humans?!

Mon, 09/02/2009 - 23:59 — bart

poo

Hi Charlotte,

Thanks for the observation. There are differing opinions on this topic, with some saying that the poo of vegetarians / vegans is 'safer', or even the only appropriate poo to use. In this case, the section on humanure was contributed by a different member than the section on composting. As this site is a user-input based format, this can happen sometimes.