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Should I Add Water To My Compost Bin?

Compost bins are structures designed to speed up decomposition. 

Bins also come in handy with preventing rats and other rodents from targeting your compost. While this depends on the kind of bin structure you have, bins make it harder for rats to get in unlike ‘heaps’ or ‘piles’.

So, should I add water to my compost bin? If your compost bin is too dry, you should add water. 

However, you should be cautious when watering your contents. 

Too much water can deprive the pile of oxygen hence enable harmful microbes to thrive. These microbes are known to produce an array of unpleasant smells in such conditions. 

Too little water can hurt your compost as well. It will take more time than expected for your pile to decompose.

In this guide, we’ll discuss the role water plays, the right amount to use, steps to take when your pile is too wet or dry, and more. Read on to find out more about compost moisture levels.

The Role of Water 

Water is a key parameter in making compost. Microorganisms responsible for breaking down organic matter in your compost pile need water for the same reason all living things do.

A steady supply of water helps the organisms to thrive, thus achieving rapid composting. Water also helps in regulating the temperature of the pile. Temperature, just like water, plays a significant role in determining the success of composting.

To maintain conditions conducive to the composting process, the pile should not surpass 140 degrees Fahrenheit. Excessively high temperatures can cause the beneficial organisms to die off. If turning the pile does not dissipate or lower the heat to at least 120 degrees Fahrenheit, water may be needed.

When the temperature drops, the compost will continue to stabilize slowly. Then after a series of chemical reactions, the organic matter will be suitable for use in your garden.

What Is the Right Amount of Water to Use?

The right amount of water is essential for compost development. According to researchers, the recommended amount of moisture content needed throughout the pile from its formation and after that should be about 50-60 percent.

But how do you test the moisture content of your compost pile? Easy. Get a pair of gloves, grab a handful of compost from the center of the pile and tightly squeeze in hand. If water flows out or more than four drops appear, the pile is too wet. If you can’t squeeze any water out of the compost, it is too dry.

The compost pile should feel damp to the touch with about the consistency of a wet, wrung-out sponge.

Too much water

As stated earlier, if your pile is too moist, it will deprive the microorganisms responsible for decomposition oxygen. As you already know by now, these organisms need water and adequate ventilation.

If your bin is sopping wet, it fills air spaces with water. Essentially, aerobic organisms will start to drown and die.

And where there is insufficient oxygen, anaerobes thrive since they do not require oxygen for growth. What’s more, they do not process the organic material as effectively as aerobes. Anaerobes release hydrogen sulfide causing your compost bin to stink.

Copyright protected content owner: and was initially posted on January 2, 2020.

Keep in mind, materials that are high in nitrogen like peaches, lettuce, grass clippings, and vegetable peelings have high water content. Hence, they should be perfectly balanced with dry carbon-rich materials.

If you have an enclosed plastic compost bin, you should be careful when mixing the fresh and dry materials. These bins let less air in, so getting the right balance of browns and greens is crucial. 

What’s more, you should avoid pushing materials down the bin for them fit in all at once. This might result in over-compacting your compost pile and lead to anaerobic bacterial growth.

While compost is slightly acidic, too much water can upset the balance. This can lead to an excessively acidic compost bin. To neutralize the acidity, add handfuls of corncobs, wood ash, and other browns into the pile to restart the composting process.


If you find your bin is too wet, aerate your pile. Using a shovel or pitchfork, turn the compost file to allow an even distribution of air and moisture. Add dry materials like straw newspaper, dried leaves, or wood chips to absorb the excess moisture. Continue with the practice until the entire pile has the same amount of dampness as a wrung-out sponge.

If you experience a lot of rain in your area, you can cover your compost bin with a tarp. Nutrients and essential microorganisms tend to leak when it rains. Too much water will also slow down the decomposition process.

Too little water

If your pile has too little water, it won’t decompose as quickly as it should. Microorganisms might not grow or reproduce as readily when less heat is generated. 

Thus, slowing down the decomposition process.

In worst-case scenarios, it can kill the good bacteria and other essential organisms; thus, you won’t get the compost for your garden.


In hot weather, some sections of the compost pile can decompose faster than others. So to avoid uneven decomposition, water the pile using rainwater if possible. Ordinary water can work just as well if rainwater is unavailable.

You should be careful when hydrating a compost bin as you don’t want to get it waterlogged. Using a sprinkler, drilled pipe as an injection probe, or anything that applies water slowly will infiltrate the pile and not seep out.

Check the center of the compost pile to ensure it is moist. If it’s dry, you may need to take a few layers off/ turn the pile, water the bottom half then add layers back as you go.

Alternatively, you can throw in some coffee grounds, vegetables, fruit scraps, grass clippings, or any other green material that has some moisture to balanced out the ingredients.

Side note: Move dry materials from the outside into the middle of the pile twice a week. Positioning the bin away from direct sunlight is highly recommended. Covering the top with a tarp is also a good idea but not necessary. It helps keep the pile cooler and moist in hot, dry months.

Also, ensure your compost bin has drainage holes to allow the leachate (a liquid that collects at the bottom of your bin) drain out. If your bin doesn’t have any opening, drill a few holes in the bottom. Moistening of the dry materials as they are added is also key to successful composting

Copyright article owner is for this article. This post was first published on January 2, 2020.

How To Know If Your Compost Is Ready

Compost can take between six months and two years to be ready. Finished or ready compost has a rich, earthy smell. It should be dark and crumbly. The pile should have shrunk by half, and most of the organic material used shouldn’t be recognizable.

What to Compost

Recommended brown materials include:

  • Eggshells
  • Straw
  • Hay
  • Wood chips
  • Pine needles
  • Sawdust
  • Paper products
  • Dry leaves

Recommended green materials include:

  • Leafy plant trimmings
  • Grass clippings
  • Fruits
  • Vegetables
  • Coffee grounds
  • Filters
  • Hair
  • Fur
  • Kitchen scraps.

Items to Keep Out of Your Compost

  • Dairy products, eggs, meat, fish bones, fats, grease, oils, and scraps all attract rodents and flies to the bin. The smell might also be a problem.
  • Some types of tree leaves like black walnut may produce harmful substances.
  • Ashes from charcoal barbecues, wood stoves, and fireplaces. Charcoal barbecues contain sulfur oxides, while wood ash is very alkaline and only suitable if the soil pH level is acidic, below 6.5. Anything above 6.5 may interfere with plant growth.
  • Waste from pets, birds, humans may contain harmful bacteria and parasites that may not be killed during decomposition.
  • Weed seeds. They may sprout after compost.
  • Diseased or insect-infested plant material. The pathogens may survive the composting process and pass it along to other plants.
  • Treated yard/plant trimmings. The pesticides might kill the microorganisms.

Final Thoughts

There’s no doubt compost is beneficial to your garden. 

While there is no right way to compost, taking the necessary measures can lead to a successful composting.

ReadyToDIY is the owner of this article. This post was published on January 2, 2020.

We hope this guide has shed some light on the dos and don’ts of composting, especially with regard to adding water to your bin.