Compost Bin Moisture Level


Compost in Bin

Photo found on courtesy of Trenttsd.

As you may know by now, moisture plays an extremely important factor in the creating compost process. In fact, it’s so important, the success your compost pile depends on it.

Don’t be scared, though. Even if you have too much water or too little, the problem is usually easy to fix after a bit of TLC. First, let’s talk about why it is bad for your pile to be either too wet or too dry.

In either situation, your compost pile will not work at optimum levels and the composting process may even come close to a stop, so keep an eye out for either situation.

Here are a few clues your pile is too moist:

  • There is water seeping out the bottom or sides of your bin or pile
  • The top layers are clumped or matted together
  • Your pile may start have a slight ammonia smell (also an indication of too many nitrogen rich materials like kitchen scraps, and not enough carbon rich materials like leaves)
  • If you bin is too wet, the water in your bin begins to deprive the microorganisms from the oxygen they need to keep working. The microorganisms essentially start to drown in the bin. An easy solution to this problem is to aerate your pile really well. Try turning the compost with a pitchfork or shovel to make sure the moisture is distributed evenly throughout the pile or bin. Then make sure not to add any more water until the moisture levels even out a bit. You may also consider adding carbon-rich materials like leaves, straw or newspaper to absorb some of the excess moisture.

    Also make sure your bin or pile is in a sunny area where the sunlight will heat up the bin and gradually evaporate some of the excess moisture. If water starts seeping out, it is most likely allowing nutrients and essential microorganisms seep out with it.

    Here are a few clues your pile is too dry:

  • The composting process has slowed down drastically
  • It looks more dusty than like fresh soil
  • There are fire ants in the pile
  • If your bin is too dry, this means that the microorganisms are going to start slowing down their process for lack of water. Just like they can’t live in too much water, they also cannot live without it, either. Having some moisture in the mix is essential to creating compost, so if there is a lack of water, your pile will slow down as well.

    A simple solution to a compost pile that is too dry is to add water. Be careful when watering your pile, though, because you do not want to drench it entirely. Instead, try showering your pile to evenly distribute the water throughout the pile. If your pile is extremely dry, you may need to take the top few layers off, water the bottom half and gradually add the layers back while moistening them down, too.

    Another way to add some moisture to your pile is by throwing in some vegetable or fruit scraps, grass clippings or any other carbon-rich material that has some moisture. When you add the nitrogen-rich materials, make sure they are a bit moist, too.

    In both scenarios it’s important to not over-compensate when trying to alleviate the problem. It may take a few days for your pile to start cooking again if it has been too dry or too wet for a while. Something to consider is adding a little bit of moisture to the pile every time you add a new layer (especially with carbon-rich materials). If you’re adding hay or straw to your pile, casually run the water hose over them for a few seconds before throwing them into the mix. You don’t want them soaking, but a little damp will do the trick.

    Once you get used to composting and seeing good results, you’ll be able to gauge the amount of water your pile needs more accurately. To help get you started on pinpointing the accurate level of moisture, you may want to try using a compost moisture meter until you get the hang of it.

{ 6 comments… read them below or add one }

Mrs.Brune October 6, 2009 at 3:57 pm

I have a compost in a tubawear box… and it is filled with rain water… yicks!!! so im going to pour out the rain water. Also before the rain stared i had mill worms in it…. Is that good for the compost? I know worms are good for it but mill worms??? Hummmm Help!


Any kind of container to make compost should have holes in it, for drainage. So you should add some kind of drainage to the box that you are using.

Mealworms are fine in compost. They are just beetle larvae.


Thanos November 13, 2009 at 9:33 pm

Hello, I’ve found an error on one of your pages… Your text reads “You may also consider adding nitrogen-rich materials like leaves, straw or newspaper to absorb some of the excess moisture.”, while it should be like “You may also consider adding CARBON-rich materials like leaves, straw or newspaper to absorb some of the excess moisture.”. The page link is

Great site by the way. Take care and keep composting!


george November 24, 2009 at 5:48 pm

Thank you. I’ve fixed that typo and appreciate your eagle eye!


Keith February 13, 2010 at 9:44 pm

Hi! Can I compost my finches bird droppings in a jar inside the house ?..With the lid on of cource !…It’s winter time now ,so I dont know if its a good idea to keep it in the cold !..I’m new to this and dont like to waist anything…Thank you !….Keith


lars March 11, 2010 at 3:41 pm

You would need to add them to a compost pile in order for them to break down. They won’t really “compost” in a jar inside.

You can bury the droppings in the dirt if you don’t have a compost bin.


Ida December 14, 2015 at 2:28 pm

I wish there was a way to print this information


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