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Tyler Ludens
Post     Subject: Compost temperature

eric koperek wrote: Don't build a compost pile unless you are willing and able to turn it.

I'm not sure much, if any, bad stuff would happen if you just pile organic material up and leave it.  Weed seeds won't be killed on the outside of the pile because of low temperature, but I'm pretty sure nothing super bad will happen.  I've made compost heaps and let them rot down with no turning.  Didn't see anything bad happen.

eric koperek
Post     Subject: Compost temperature

TO:  Dar Helwig
FROM:  Eric Koperek =
SUBJECT:  "Rinky-Dink Compost Pile"
DATE:  PM 6:05 Wednesday 7 September 2016

(1)  There is no one, right, true, and God-ordained temperature for a compost pile.  Required temperatures are dependent on what you want to accomplish.

(2)  Traditional composting practice requires a pile measuring at least 1 cubic yard (3 feet long x 3 feet wide x 3 feet high = 27 cubic feet) in order to hold enough heat to kill pathogenic organisms.  Minimum required temperature for compost pasteurization is 130 degrees Fahrenheit for 1 full month = 31 days.  

(3)  Compost temperature is highly dependent on nitrogen concentration.  Translation:  If your pile does not heat up, add more manure or other high-nitrogen materials.

(4)  Turn compost pile immediately temperature reaches 160 to 165 degrees Fahrenheit.  This is a very hot compost pile.  For best results, turn compost pile every 2 or 3 days for 1 full month = 31 days.  Do not let compost pile heat above 160 to 165 degrees Fahrenheit.  You don NOT want a "runaway" compost pile.  When in doubt, turn pile to increase oxygen content and moderate temperature.  

(5)  Turn compost pile every time temperature spikes.  This temperature will vary depending on the mix of materials in your compost pile.  Your temperature may spike at 140 or 150 degrees Fahrenheit depending on the amount of nitrogen available to fuel decomposition.

(6)  Composting is a controlled oxidation process = burning.  Translation:  Decomposition is dependent on air supply (just like a fire).  Do not chop, grind, or shred ingredients finer than 1 or 2 inch size pieces.  Very small bits of organic matter will pack together and restrict oxygen supply to micro-organisms.

(7)  Stinky compost piles have too little oxygen.  Turn compost immediately.  Stinky compost is BAD compost = not good for plants.  You want AEROBIC compost = made with lots of oxygen = not stinky.

(  For most folks, turning compost piles is a drudgery best put off to another day.  Don't build a compost pile unless you are willing and able to turn it.

(9)  There are alternatives to traditional = much labor composting.

(10)  Sheet composting = cold composting is ideal for growing fruit trees, berry bushes, grape vines, and most perennial garden plants.  Simply pile organic materials in thin layers on top of the ground.  Stop adding materials when pile reaches 12 inches = 1 foot deep.  Pile will settle to 6 inches deep in a few weeks then you can add more material if you feel like it.  Think of sheet composting as a form of deep mulching.  Materials decompose slowly at ambient temperature = cold composting.  No turning required.  Just keep ground covered with organic wastes at all times = add more mulch.  Limestone, rock dusts, and other fertilizers can be spread right over the mulch.  No mixing or cultivation needed.  Stinky materials (like fresh manure) should be buried underneath the mulch.

(11)  Sheet Mulching = Year Round Mulching is a very old horticultural technology dating back to the Middle Ages.  Small farmers and "cottagers" who did not own animals fertilized their land with "green manure" = grass, weeds, and leaves gathered from hedgerows, road sides, forests, and hillsides.  Rich farmers fertilized their fields with dung.  Poor folks used mulch.  The Medieval standard was "2 hands high" = 8 inches.  Spread organic wastes over your garden 8 inches thick.  Mulch will settle to about 4 inches thick in a month or so.  Add more mulch as needed to maintain proper depth.  If a weed pops up, smother it with more mulch, pull it out, or leave it alone if not crowding your crops.  (Widely spaced weeds, about 1 every 3 feet are good for your garden).  Keep ground covered with mulch year-round = 365 days annually.  Pull aside mulch only enough to sow seeds or set transplants.  When crops are well established, pull mulch up close to plant stems.  THE PURPOSE OF YEAR-ROUND MULCH IS TO FEED EARTHWORMS.  Worms will till and fertilize your garden = less work for you.  Just keep adding mulch.  Irrigate when weather is dry.  Sprinkle fertilizer (if necessary) directly over the mulch.  You can run small market gardens up to several acres in size just by growing crops in year-round mulch.  By keeping your garden mulched you can increase average topsoil depth by 0.20 to 0.25 inch per year (depending on amount of organic materials added).

(12)   For really small gardens try blender composting.  Buy a blender specifically for this purpose (to avoid possible bacterial cross-contamination).  Liquefy kitchen scraps or weeds to make "blender soup".  If you have a good blender you can grind up chicken or fish bones, also.  Pour blender soup directly on soil surface then cover with a bit of decorative mulch = just enough to keep any flies away.  Finely pulverized organic materials decompose swiftly = usually within 1 week during warm weather.  In tropical climates, blender soup can disappear in a few days if poured directly on top of soil.  Use blender soup like liquid fertilizer to feed your tomatoes and other garden plants.  Blender soup is ideal for plants (like roses) that are sensitive to excess nitrogen.  Blender composting is another form of cold composting but the rate of decomposition is much faster because organic matter is reduced to fine particles that are easier for bacteria and fungi to eat.

(13)  Decomposition will proceed at any temperature above 40 degrees Fahrenheit.  If you want to kill pathogens compost must reach at least 130 degrees Fahrenheit for 1 month.  If you don't have any virulent diseases to worry about, composting can take place at ambient = air temperature.

(14)  From your description it seems that you do not have sufficient volume for a functional compost pile.  Consequently, I recommend that you just spread your leaves and grass clippings around your shrubs or over your garden.  If you need a little compost for your houseplants or greenhouse just rake aside some mulch and scoop up a little topsoil from your garden.  Your plants will not notice the loss.  The earthworms will replace what you take in a few years or less.


end comment


Dar Helwig
Post     Subject: Compost temperature

I have had a rinky dink compost pile for 2 years now. Started out with about a 6ft x 6ft leaf pile. The next year it was down to about 2ft square. So I knew it was working. Never got around to adding a lot to it. This year I added a little straw and hay (mulched with my $10 gas mulcher) and a couple wheel barrows full of fresh cut grass (mixed in well). That was just about 6 days ago. I just noticed the pile is hot inside. I stuck in a thermometer with one of those long wires leading to a sensor and found that the temp in the pile is 130 degrees. Yippee! I think this is really good. What is the best temp range?