The heat phase is but one of several. The curing or maturing phase can be much much longer and is just as important.

http://compost.css.cornell.edu/microorg.html

Yeah. I don't think that there's a firm time when compost is ready, except that if it's still cooking it's definitely not ready.

The compost I made for large containers last year has considerably more oomph to it this year, even though I went fully through the cooking and mellowing rigamarole back then. That's common.

I use N fertilizer to fire up my pile and add small maintenance doses in advance of rain storms after the heat subsides.

If you are looking to keep "cooking" your compost pile you need to turn it. The thermophilic bacteria that are doing the bulk of the composting when a pile rises about 110f need food and air as well as some moisture.

It sounds like you have done a great job getting this composting thing going. Here are some basics that may help get you to the next level.

All sorts of organisms can participate in the process of breaking down vegetation, but the two massive contributors are bacteria and fungus. The bacteria grab the easy stuff and can raise the temperature of the pile as they work. (Compost piles don't have to get hot, but they decompose faster if they do.) If you carefully manage the pile you can graduate to bacteria that only become active at relatively high temperatures. Those colonies of super bacteria can break things down quickly, reducing the volume of your pile in half in about three weeks.

However, whether the bacteria are working fast and hot, or slow at more moderate temperatures, they come to the point where they have consumed all the easy stuff and much of what is left is the harder woody structures. Bacteria can't digest that, but fungus can. That's the point that fungus takes over. Fungi do not work quickly and there are no tricks to speed them up (other than add a greater variety of them). Fungus will feed for another six months to two years converting that woody material into crumbly sweet smelling humus.

Humus is the end product of composting. It is the final state of decomposition and is very stable. It can stay the same for thousands of years. Most home composters, however, don't wait for perfect humus. They take the unfinished compost and add it to their gardens where it continues to break down there. There's nothing wrong with that as long as you are aware that your compost is still chemically changing and make allowances for that.

So, your pile is just moving over to the fungal stage which means it is right on schedule. Give it at least a couple of months for the fungus and earthworms to take a whack at it. It should be ready to add to the garden in the fall, or you could wait until spring.

If that compost is not finished then the bacteria do not have enough food, air, or moisture to function, or the process is past the thermophilic phase and into the mesophilic phase. If adding a source of Nitrogen does not get things heated up then the compost is beyond the thermophilic phase.

Keep in mind that what is on YouTube may not be the best information source. Perhaps this tutorial will be of some help.

http://sarasota.ifas.ufl.edu/compost/

kimmq is kimmsr

A couple things: Good luck getting fungus going in Phoenix.

Second, what's so important about getting the temp up again assuming that the pile achieved high temps for a few days? As that excellent article implies, just try and keep the ball rolling.

PS. I suspect in Phoenix, that the pile dried itself out between the high ambient heat anid its own temps

It does need an extended period to finish. Compost is not instant satisfaction, it takes a little time. If it heated up nicely then you had enough greens. Without having seen a picture, I suspect you should not add anything else, make sure it is moist, and let it be for awhile. Things are happening, but they are not as obvious as a plume of steam. Starting a new pile was a great idea. Concentrate on adding to that and let the other one be for a bit.

Thanks everyone! I knew it needed to cure, but I was under the impression it was supposed to be more uniform-looking by that point. I'll keep it moist and let it do its thing.

toxcrusadr, don't worry, I gave up on instant satisfaction long ago! The bulk of this pile is actually past 2 years old because I was doing it wrong for a long time. I first had it in a trash can which was too small to heat up, I neglected it thinking it would cold compost, and came back to an anaerobic mess instead, so I wondered if it was just worn out from its journey through my learning process before I finally figured out how to heat it up properly.

kokopellifivea - you're right, I think it was drying out too much. Most guidelines don't have climates like mine in mind so I've started upping my watering to compensate.

You mentioned an important phrase up there -- "keep adding greens". I hope you are also adding browns, of which there should be much more browns than greens. for example what I mean by that is that if you're seeing something which looks like it's done or crumbly, you still need to replace what is now gone, so continuing to add browns and greens should help it along.

In Phoenix you have to work at maintaining the moisture level, AND accept that the sides of the bin aren't going to compost much, leaving a 6-inch rind of dry material. You will get a core of the "good stuff" and have to run the rest around again in the new bin.

I had my compost bins on one of the drip irrigation stations with a loop of driipper tubing on the top to keep it moist.

Taking apart a heap, showing the core of finished compost.

http://1.bp.blogspot.com/-XJUJmVYvOMk/VU9hU3YYRgI/AAAAAAAAAVk/Oq8XqsTegnI/s1600/compost2.jpg 

I would not keep adding browns and greens to a pile that was started 2 years ago. It just prolongs the finishing process. That's a long time and the stuff that initially went in has been shrinking and shrinking. When compost is 'done' it does not stop. It continues (albeit slowly) to release CO2 and water in the process of becoming indigestible humus. Nutrients leach out as well. This decomposition process itself is beneficial to plants while it is occurring. IMO it's best to use it as soon as it has reached a crumbly stage.

Note that you could probably also use this not quite finished pile now as a mulch/side dressing. Or if it was fall you could dig it into a garden bed and by spring there would be no sign of it.

I prefer to put compost to work rather than wait around.

Just because the pile has cooled down doesn't mean it can't heat up again. There are several factors that cause the pile to cool down. It could be low oxygen, not enough moisture or even not enough fuel. The thermophilic bacteria is mostly working at the center of your compost pile. In order to feed it oxygen and moisture you need to turn it as soon as it starts cooling down. This will bring in more oxygen and fuel (from the outside edges of you pile that did not heat up) and while you are turning it give it some water. If it still isn't heating up at that point that means that the hot phase of your compost pile is complete.

The term "curing" used in relation to compost is probably not something that should be. One site that talks about "curing" compost says the compost needs to be "stabilized" so it does not decompose more. In my experience compost put into the soil will be decomposed more and that is why we need to replace it often. Another site talks of a 4 month "curing" period for compost with animal manures mixed in. Otherf sites discussing "curing" compost speak, in my opinion, nonsense.

Compost is finished when it is mostly digested, is cool, is moist, and smells like good rich earth. At that point put that compost in the soil where it is needed to replenish the nutrients used by growing plants.

Some will try to tell you that you cannot put "uncured" compost in the soil because that will cause all kinds of problems. However, I have tilled in cover crops (raw plant material) many times and had no problems. I have put "uncured" compost in my planting beds quite often with no problems.

kimmq is kimmsr

One only has to google "uncured compost" to find many references from reputable sources with several of them explaining the potential problems of using said material. Curing is a commonly used phrase in the composting world just like browns and greens.

Well, there is the public health issue of growing food in soil where there is fresh animal manure. That's different.

Instead of "curing" a better term is "usable" meaning to me, "may be added to the soil without supplemental amendments."

I stand by my observation from container growing, which is that the stuff is better the second year than the first. That's not an argument for waiting two years before using. It does suggest to me that useful decomposition takes place after the stuff is "cured" that should be managed.

For me, a non-organic guy, in my climatic conditions and very woody pile, that means adding soluble N-0-0 fertilizer in low doses, (50-100 grams at a time) and keeping the pile damp, even after it has "cured".