Compost Making FAQ
Downloaded 02/25/02 from http://www.oldgrowth.org/compost/
Tue Nov 29 19:37:38 EST 1994
Article: 48571 of rec.gardens
(Michael E. Matthews)
Subject: Making Compost FAQ (long)
Date: Mon, 28 Nov 1994 20:48:48 GMT
The following is a collection of composting advice from Jim
McNelly, aka Mr. Compost. Long-time readers of rec. gardens
will know him well. It is a compilation of some of his replies
to various questions from this group. It contains the
essentials of composting. If anyone has other of his posts
saved, I would sure like to recieve them.
Michael Matthews in central VA
Subject: Composting 101
Date: Thu, 19 May 94 02:51:00 +0600
Organization: Granite City Connection St. Cloud MN 612-654-8372
As requested, here is my recipe for home composting.
Mulching (leaving things in layers) is easier than "piling"
organic residues, but there is a place for passive compost
piles as well. But for those who desire to make an active,
hot, compost pile that is ready for curing in three to four
weeks, here is my tried and true formula for cooking hot
Active composting is a BATCH process. It differs from passive
piles that just sit there or continuous flow systems where
stuff is periodically dumped on top of the material already in
1. PREPARE THE AREA: Avoid walls and fences that can rot and
discolor. Stay within reach of the hose. Choose a spot away
>from drainage swales and roof overflow. Avoid low spots where
water can stand or pond. Leave plenty of room to access with
pitch fork and wheel barrow. The area should be from 6'x6' up
2. CHOOSE YOUR BIN. Small yards use enclosed plastic,
preferably insulated bins. Large yards use larger open air
designs without covers. Large doors are better than small ones.
Three stage systems are best, but only one, maybe two bins are
active at any given time. The three stages are stockpiling,
active composting, and curing. Curing piles do not need bins.
3. STOCKPILING: Since active composting is a batch process, it
requires a full bin of material and this usually requires
stockpiling. Materials easy to store include leaves, wood
mulch, pine needles and cones, old compost, and shredded paper.
4. INOCULATING: Active composting is helped by adding old
compost or leaf mould as an inoculant. This can range from 10%
up to 50% from the curing pile or the still-cooking, last
batch. Avoid soil except as a last resort. Use bagged compost
or manure if starting for the first time. Packaged inoculants
do no harm, and may even help, but are not a substitute for old
5.MIXING and 6. WATERING: Layer your various ingredients
OUTSIDE THE BIN, watering each layer as you go. Think "Green
and Brown". Add 10% bulky matter like wood chips to keep the
pile loose to avoid matting. THEN fork the layers into the bin,
mixing as you go, blending wet with dry, watering as necessary.
Water like a seed bed, avoiding runoff. The mix should end up
50% moisture like a damp sponge. Now and during the 3 weeks of
active composting is the time to add table scraps. Avoid adding
lime, it can disturb the natural pH shift and delay
7. AERATE: Like any other form of livestock, your "herd" of
bacteria needs food, air, and water. You have added food with a
balance of carbon and nitrogen, which is the green and brown.
You just added water. Now the bacteria need air. Old compost
theory suggests that you "turn the pile for aeration; recent
studies show that a pile uses up its oxygen in as little as 1/2
hour after turning.
Like a barbecue or a fireplace grate, a pile needs ventilation.
This is provided through a passive aeration base. Some use
brush, stalks, screen on boards, rocks, wood chips, flat
aeration pipe, other mechanism to let air infiltrate at the
base from outside. The air will rise up due to the convection,
chimney effect, of warm air rising. With wood chips added, the
pile will self aerate with an aeration grate without turning.
Poking the pile from the top down to the base with a piece of
rebar or 1/4" rod every 6" will break up mats and provide extra
The pile will begin active composting within 48 hours and cook
by itself. You can help the process by mixing at least once
after a week, sort of like stirring the coals, adding moisture
as necessary. When it is not frozen outside, I make a compost
batch every 2 weeks, often using half cooked compost from two
weeks previously to mix with the fresh grass clippings.
Personally, I bag my grass because I like making and using
compost, but letting the clippings lie is a fine way to avoid
the effort of active composting.
Follow these steps toward batch composting and you will see the
pile heat and cook, giving off the steam of life as it
decomposes. I think everyone should experience the pleasure of
having a compost pile cook well at least *once* in their lives.
Two last tips, *underwatering* is the largest single cause of
slow composting. Piles in *standing* water is the number one
cause of odors.
Granite Connection 612-259-0801
* May 19th - What's all this fuss about endangered feces?