With the millions of organisms in the compost, I don't think you will get a 'one size fits all' kind of answer.

Some will die, some will go dormant, those that can leave will try to leave, etc. etc.

Other than to reduce transportation costs or make it easier (lighter in weight) to handle, I don't know why one would dry out compost before using it. I know I don't.

Lloyd

I left one of my compost bins uncovered in the end of winter because it had become dry, and we had a wet spring. Too wet for the compost. It will need to dry out a bit before it will finish composting.

I also now have a large pile of manure. It, too, will need to dry up quite a bit before it will ever finish composting.

Wet and dry are relative to what the compost needs. And once the compost has finished composting, it will tend to hold moisture.

You're supposed to dry it out first?

Dang. I've been doing it wrong for decades. I use it as-is, although I'll sift it if I'm spreading it on the front lawn.

It's easier to rake out if it's not soggy - that's all.

I guess I had never heard that but people tend to say a lot of things other than the very simple reasons listed above use it when it seems good to you

The bacteria that digest the material you put in to become compost need some mosture to function, not a whole lot, but some. Drying compost would cause some of those bacteria to die and others to go dormant but if you are going to spread this compost onto your soil, where it would become moist again, there would be no real benefit to drying compost before putting it onto your soil.

Okay, thanks everyone! Maybe I just happened to read comments from people who were about to spread it out thinly and needed it drier to spread. I'll keep on using it "as is" to build up my raised beds.

It is easier to sift/screen if it's drier, maybe that's where you saw the reference to being drier but I wouldn't dry it completely even to sift, way too dusty.

Lloyd

I read that you should dry it if you are going to store it in bags or buckets. If it is too wet before storing, it said that the compost can get sour or stinky from being enclosed while too wet. That said, I can't figure why someone would want to store it in a bucket or bags. I can't wait to get mine out into the garden.

I sometimes dry seedless weeds so they wont root in there. If they take root it takes longer for them to die if the bin is not hot. You will learn if you have hard to kill weeds.

If you put your compost where it belongs, on your garden, there is no benefit to drying it. However, if for some musguided reason one were to store that compost then drying would be beneficial because the presence of moisture would allow the bacteria in that compost to continue digesting it so when you came back to use this stored compost you may not have any, and possibly the storage container could cause the compost to enter anaerobic digestion and it would stink. This is one reason why the bagged compost from the stores smells bad, anaerobic sigestion.

I found a 45 gallon (canadian gallon) drum of compost I had put in a shed at least 3 years ago. The top 3-4 inches were dry like dust but the bottom 3 feet were still moist. It hadn't shrunk much, maybe 5-6 inches if the barrel was full when I put it in the shed. Smelled just like fresh compost so it didn't "enter anaerobic digestion".

Now my compost is well cured when I'm done so the oxygen uptake is very low. If the compost isn't cured to a very mature state and then stored or bagged, I'd guess there would be more risk of shrinkage and possible anaerobic problems. So maybe if a person is storing 'not quite done' 'post then drying down might be an idea.

Lloyd

If I wanted to make a dry mix that can be stored and brewed at a later date would the important organisms die off too much to use? Seems hard to store all components wet. And has anyone every use powdered fish instead of liquid? Im trying to use all powders..