Decado
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Heating Up Compost Barrel

I've been turning my barrel every few days but it doesn't seem to get much hotter than it does outside. I have various weeds, dead stuff from last years flower pots and rootbound, unusable potting soil in there. What Should I add to heat it up? Grass? Note that I don't have a whole lot of space left in there.

tomc
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Compost needs to be a bit bigger than one cubic yard in order to heat up. The classic compost built out of old pallets is (roughly) 4 feet, by 4 feet, by 4 feet. A fifty-five gallon barrel is only about 1/3 the volume needed.

You could lock on the top of a 55 gallon drum and just let it (anerobicaly) rot for a year or two. It will get close, but its stinky and slow.

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rainbowgardener
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It is hard to get a small volume of material in a barrel like that to heat up much. But that doesn't really matter, if you have a good mix and it is aerated, it should compost anyway. My compost pile often doesn't heat up very much, but it breaks down well. But it sounds like what you need is not grass, but more "browns" - carbon rich materials. Everything you mentioned so far: weeds, dead stuff from last years flower pots and rootbound, unusable potting soil, is "greens." (Check out the greens/browns sticky at the top of this Composting Forum.) If the potting soil is full of roots, the roots can break down (loosen it up first). But soil is pretty much in its broken down state already. If you put very much potting soil in compared to the volume of everything else, it will just slow everything down. It is not adding greens or browns or anything much else.

So add browns, I.e. fall leaves, shredded paper, straw, cornstalks, etc and toss well. Since it isn't heating up much, it would help to throw some earthworms in. Much of the composting in my pile is actually done by earthworms and other detritovores.

Decado
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Ah well I guess that straw I just got will come in handy here. Now my only concern is seeds (especially if I use this straw). If the compost can't get above 130 degrees will I have seeds popping up all over once I put this compost down?

Susan W
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If you have even a small area in your yard, could do the 'enriched dirt' pile. Mine is fairly big, back in a corner, part sun,. As I do lots of container gardening, have a fair amount of dumped pots, or at least changing out the top few inches. I keep adding the pot stuff. Add kitchen scraps nearly daily, cover with a forkfull of the dirt, often turn it down a few inches. The worms are very happy! The pile is actually more like 2 now. Using off one side, adding stuff to other. When that gets low, switch back. As it doesn't get really hot, don't add weeds. Grass clippings stay where they belong on the lawn, using the mulching mower. In the heat of summer the worms go deeper and are less active, and they stay deep in the winter. Come spring they reign!

I am looking to get a tumbler, but that is a different thread.

toxcrusadr
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Straw should not have a lot of seeds in it - it's the stalks of wheat, and the wheat seeds are the crop, so there should not be many. Hay is grass and is full of grass and weed seeds.

The other posters covered the size and green/brown issue. I also wanted to point out that potting soil is basically already composted, so although it doesn't hurt the compost (I sometimes add it, especially really old, worn out and crusty stuff), it's almost like adding finished compost so it will not provide green, brown or heat-making capability. But don't worry, your compost pile does not have to get hot to make compost.

Decado
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I know straw should not have seeds that's why I bought straw and not hay.



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