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I just started composting a month back and have some basic questions. I have been putting garden and kitchen waste in my compost bin every week. I have been turning the pile every week to mix up the ingredients and to make sure flies and insects (which have started to appear) don't get a chance to lay eggs and multiply.

  1. Typically how long does it take for compost to form so I can remove it and use it?

  2. If I keep turning the ingredients, I will never get good compost because it will be a mix of fresh ingredients and compost.

I think I am doing something wrong and looking for guidance

  • From what I've read here it can take months, but I'll let someone more knowledgeable reply in more detail :) – Tim Malone May 19 '16 at 19:41
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    Let's put it this way: you really need three (or more) piles: one that is ripe and you are taking material from, one that you've stopped feeding and are allowing to mature, and one that you are feeding. – dmckee May 20 '16 at 2:24
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    @dmckee is right though you can get away with two piles (or bins) if you store the finished compost in sacks. – Chris H May 22 '16 at 12:51
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I agree with Organic's answer about the ratio of materials in a compost pile. The trouble is, you're adding stuff whenever you've got it, like most of us do, and most instructions for 'efficient' composting are expecting you to have quantities of so called browns and greens all at once, and mixing them together all at once, then turning regularly, without adding anything else. Because a compost pile that's turned regularly, with the right moisture level and kept covered to trap the heat, becomes aerobic and hot, the resulting compost is ready much quicker - 3 to 6 months, depending on air temperatures where you are, and if you are able to turn the pile at least twice a week.

However, if you're adding stuff and turning it regularly, then you will inevitably end up with some parts composted down into blackish soil (that's what it looks like when it's ready), mixed in with other, as yet uncomposted material. Some compost containers have a door at the bottom on the front - this is to allow you to get at the bottom of the heap, which will be ready before the rest of heap, so you can remove what's ready and leave behind what's not. But usually, that sort of compost arrangement is aimed at creators of cold, anaerobic heaps, where its not turned regularly and just left to rot down quietly on its own, with stuff being added all the time on the top. After a year or two, the stuff on the bottom is, of course, ready for use when the top is still covered in fresh materials - cold anaerobic composting is fine so long as no weed seeds or diseased materials have been added, you're prepared to wait longer, and you're not intending to use the compost for anything other than adding back to the soil in the garden/yard. If that's not the type of compost bin you've got though, then you either wait till its full and all composted and then use it, or try to sift through and extract what's not ready for use after spreading it and replacing the uncomposted stuff in the compost bin.

Many people get round this problem (if they have the room) by having more than one compost pile or composter - they fill one up, then start the next, not adding to the first one any more, just turning it regularly, then when its ready, using the contents, and then start another compost pile in there when the second bin or container is full. If you have a lot of stuff to compost, then three compost bins works really well, but most of us don't have those sort of quantities.

You're not doing anything wrong as such - in an ideal world, you'd have masses of browns and greens all ready at once, 3 compost bins and the ability to construct the right sort of pile of compost in one go, but the world is not ideal, and for most of us, we do what you do. But however you do it, you will eventually get useable good stuff from the compost bin.

  • You are right, we are expected to have greens and browns. I buy wood shavings from the pet store and throw them into the pile every time I add greens. Wood shavings are widely available and a great source of fertility once decomposed. – Organic May 22 '16 at 13:48
  • You might be better off asking if you can take away their spoiled straw using for animal bedding. – Graham Chiu May 26 '16 at 15:40
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It'll depend on your climate and on how warm/active your compost pile will get. For best results you should also ensure that you have the right ratio of greens and browns.

Your composter or compost pile needs a proper ratio of carbon-rich materials, or “browns,” and nitrogen-rich materials, or “greens.” Among the brown materials are dried leaves, straw, and wood chips. Nitrogen materials are fresh or green, such as grass clippings and kitchen scraps. [...] The ideal ratio approaches 25 parts browns to 1 part greens.

http://compostguide.com/compost-materials/

Compost can be ready within a year if the conditions are right but it may take longer. You'll know it's ready when it is all broken down into small particles that look and smell like soil without any unpleasant odour.

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To do it efficiently you need to monitor the temperature of your pile. If it never heats up, you have too much carbon material present. If it does heat up, but then cools down, then that's when you need to turn it so that fresh material is ready to be moved into the centre of the pile with more oxygen.

So you need a thermometer. An oven meat probe on a stick might work.

Or just let it sit for a year without turning it at all, and use it then. Everything decomposes in time without our intervention.

The point of getting carbon nitrogen ratios right, and turning, is to optimise the process, and avoid losing too much nitrogen from oxidation, and loss to the atmosphere. Or ending up with an anaerobic stinking pile due to too much water, nitrogen, and not enough oxygen.

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