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How do I know this is good compost?


By Lori


What does it mean if it smells? or if it’s too wet?

I had questions and decided to read-up. Found a number of publications… most down-to-earth was Rodale Press.
One interesting tidbit was a lady from North Carolina who was able to produce her compost in black plastic bags..She filled the plastic bags with “damp garbage, grass clippings, a little stable manure, soil, dried up flowers, rinds, eggshells”; sealed the bag and placed it in the sun..It was light enough for her to turn easily and a sequence of four bags in cycle actually produced compost for her city garden and relatively quickly, too.
But the most interesting thing I found was a method to evaluate your compost and make sure your methods are sound.
1. the compost should be without lumps, clumps or packing. It should be crumbly.
2. The compost should be black-brown. If it’s pure black it means you have had insufficient aeration and fermentation has taken place because of too much moisture. If it’s yellow/gray it’s dead.
3. It should smell earthy, humusy. Any bad smells indicate that the bacteria are still active. Mustiness can indicate moulds, mildews, or the product of a hot fermentation which burns off the nitrogen.
4. The pH should be neutral to slightly acid. Nitrobacter and earthworms prefer this range. pH below 6 is too acidfor nitrobacters but if you want acidic compost for potatoes, azaleas, rhodos, etc. you skip the lime and add leaves and conifer needles.
5. getting the right proportion of components is important..
the Organic matter: garbage (veg. peelings, rinds, fruit,veg,weeds, manure, leaves (carboniferous stuff) should make up most of the first layer. next is soil, old compost (starter),and lime. (they suggest if you have to use sub-soil or pond scrapings that you allow a freeze thaw cycle to sterilize(?) the material before adding it to your compost.)

6. Getting the right amount of moisture is crucial.. It should be moist enough to clump together under pressure, but the lump should disintegrate when pressure is released. It must NEVER be dry…too dry and nothing happens, but conversely if it drips it will ferment. Sometimes when it starts to cook and is producing too much heat you have to fork it over and add a little water. Keep it aerated.

7. If you’re going to use earthworms in your process get the right type…common earthworms (lllumbricus terrestris) will not stay in your compost or manure pile, they come for dinner and leave after dessert!..Experts suggest red worms (Lumbricus rubellus) sold by breeders(!!) " red wigglers, Georgia reds" (If worms interest you read “The Earthworm Book” by J. Minnich) Info is available about this method of composting called the Indore method. It is the worm castings that enrich. You can build Earthworm bins and pits and even compost indoors with red worms all winter long in cold climates…

Well back to the books…

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Thanks Lori, this is very useful information. I will keep a copy and use it as a useful reference for the future.
Obtaining the right quality of compost is so important to the health and well-being of plants.
Kind regards and best wishes,

10 Mar, 2008


Grass clippings, vegetable peelings, shredded plant material, small amounts of cardboard, tea bags, shredded paper all go on mine. There are earth worms and even slo worms have been found. It rots down and is used. I know it's not the most perfect compost but I have a mutitude of plants trying to grow in it. I saw a parsnip top today trying to survive along with potatoe peelings.
one day i will have that perfect crumbly stuff.

10 Mar, 2008


Yes Trees...we all have our personal style.
happy composting.

10 Mar, 2008


Thanks for posting this Lori. I enjoyed reading.

10 Mar, 2008


A very interesting blog, Lori, thank you.
A couple of years ago our local council supplied 'green' bins' and required us to use it for compostible garden and kitchen waste. They collect the 'black' bins (non-compostible waste) and 'green' bins alternate weeks. I found this move rather galling because I had been composting my garden and kitchen waste for yonks so effectively my service was halved (my 'black' bin is now emptied fortnightly instead of weekly) and there was no way I was going to get rid of stuff that my garden benefits from.
I have continued to use my old compost bins as usual and now use the 'green' bin to produce a mulch for azaleas, pieris etc.

11 Mar, 2008

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