Last week, Kompost Kids answered your composting questions in the first episode of Ask Them Anything! They provided tons of incredible information for us. Thank you so much for your time and expertise, Renee and Marion!

I put together this recap for you based on the answers they provided. Want to hear their full answers? Check out Part 1 and Part 2 of the episode to listen in!

For more information about composting and step by step directions, check out the How to Compost in Milwaukee Guide.

General Composting Info

Why is composting important?
  1. Compost is a great soil amendment for gardeners. It adds nutrients and beneficial bacteria back to the soil to help plants thrive.
  2. Food waste produces methane when it breaks down in a landfill. This is a potent greenhouse gas that is contributing to climate change.
How long can Earth survive without composting?

It’s impossible to say for sure, but life on Earth won’t survive forever without it for two reasons:

  1. Organic waste produces methane when it decomposes in landfills. Methane is a potent greenhouse gas that is contributing to climate change.
  2. Top soil is being depleted by current agricultural methods. Compost helps preserve and amend top soil to allow us to continue to grow food to survive.
What is the difference between backyard and commercial composting?

Commercial composting is able to process organic materials, even materials that may contain pathogens, to produce safe compost. Commercial composting is done on a large scale, gets hotter than a backyard compost, and is tested throughout the process to make sure it is safe.

Backyard composting is what you’re able to do safely at home. The compost isn’t tested, so do not add items that may contain pathogens. Add vegan (plant-based) items and eggshells.

Home Composting Options

How do you start a successful backyard compost?

Organic waste is predisposed to decompose – no matter what. Don’t overthink it!

Decide how much time and effort you want to put in, and where you want to compost in your yard. Make sure it is accessible so you can add to it and maintain it.

If you have a smaller space and want low maintenance, cold compost with a compost tumbler or bin, or build your own! This is recommended for beginner composters. Check out the How to Cold Compost guide for step by step directions and information.

If you have a larger space and are able to maintain it about once a week, hot compost with a multi-bin system. Check out the How to Hot Compost guide for step by step directions.

Layering is key! Every time you add greens, top it off with double the amount of browns. Maintain a 1:2 ratio of greens to browns as you layer. End with a brown layer to deter pests, and use a lid.

A sunny location is ideal, but not required. You may need to water your compost if it dries out. Putting it in a location with easy access to water is helpful.

Can you compost in small gardening spaces?

Yes, but explore all of the available options to see what works best for you. Decide what you’re comfortable with in your space. Tumblers and plastic bins work well in small spaces, but they tend to be more anaerobic because they are so enclosed. This means they can be wetter, muckier, or stinkier.

If you’re ok looking at the compost, a wire bin is less anaerobic.

Can you compost in apartments without outside space?

Yes! Check out the How to Vermicompost guide to get started.

Things to consider:

  • Worms are living, so they do require more care and attention than cold composting.
  • You may need more bins and worms if you have a family larger than two people.
  • You have to have an outlet for the finished vermicompost.
Can you compost in small spaces, like a balcony?

Yes! Check out the How to Vermicompost guide to get started.

Things to consider:

  • Worms are living, so they do require more care and attention than cold composting.
  • You may need more bins and worms if you have a family larger than two people.
  • You have to have an outlet for the finished vermicompost. If you are growing food or plants on your balcony, this is a good outlet.
What if my worms aren’t able to keep up?

Consider getting a bigger bin with more worms. Using a stacked system or more than one system will allow you to process more food.

Compost Maintenance

What can you and can’t you include in a compost?

Keep it vegan, plus eggshells. Don’t add things that could carry pathogens like fats, oils, dairy, animal products, and pet waste. For a detailed list, check out What’s In/Out? on Kompost Kids’ website. Learn more about “greens” and “browns” in the How to Cold Compost guide.

What about…

  • Pet or human hair?
    Not recommended. It can attract pests for nesting and create an anaerobic condition.
  • Dryer sheets?
    No. Dryer sheets are toxic.
  • Dryer lint?
    Not recommended. It may be toxic due to dyes and microplastics in clothes.
  • Ashes?
    Not recommended. Unless you know there isn’t any lighter fluid, the wood is untreated, no paint, etc. Ashes from a charcoal grill contain petroleum and should not be added.
  • The contents of a vacuum bag?
    Not recommended. It may contain microplastics or other toxic materials like paint, plaster, etc.
  • “Backyard compostable” items?
    “Backyard compostable” is not a recognized certification, so we can’t say for sure. We’re not sure who is managing it or deciding what the standards are. BPI certified bags do compost, but they can be gelatinous.
How often should you turn your compost?

You can turn your compost as often as you’d like! Turning the compost introduces more air, which heats up the pile and speeds up the process.

If you want to slow compost, you don’t need to turn it at all. If you want to hot compost, turn it about once a week when it cools off. If you have a compost thermometer, turn it when the temperature drops below 130ºF.

If you don’t turn it, a slow compost system will produce finished compost in 12-24 months.

How often should you water your compost pile?

Your compost should be as wet as a wrung-out sponge for active decomposition. With Wisconsin weather and the moisture in food, you may not need to water your pile at all!

If the compost dries out, you can water it until you see water starting to seep out the bottom. Or, let the weather take care of it! Decomposition will happen again when it is wet enough.

How do you prevent issues with pests?

Compost can be appealing to critters looking for warmth or food. You can deter them by making sure your container is enclosed. Mice can’t fit through holes 1/4 inch in diameter. Covering food scraps with 3 inches of brown material helps hide desirable food.

Critters are attracted to yummier fats. If they become a problem, don’t add eggshells.

If you start composting in the spring, when will you have compost to use?

Hot composting can produce finished compost as quickly as 6 weeks!

Cold composting, without any turning, can produce finished compost as quickly as 12-18 months. This is a great timeline for when you start gardening the following spring!

Does compost need to rest or mature before using it?

Your compost is ready to use when it looks and smells like dirt.

Finished compost will crumble between your fingers. It’s damp, but not slimy or clumpy. It will smell earthy like after it rains, not acidic or vinegary. You might see some worms, but you shouldn’t see a lot of them.

Can you use compost that isn’t finished yet?

If you amend your soil with unfinished compost, you can scorch the roots of plants when you plant them. This can kill seedlings and seeds. A good way to check your compost is to see if a radish seed will sprout! If you amended your soil with unfinished compost, don’t plant into it right away. Give it a couple of months to finish before planting in it again.

Mature and well established plants can handle unfinished compost if used as mulch or topdressing.

Is it possible to compost outdoors year-round in Wisconsin’s climate? 

Yes! A hot composting system will maintain its heat throughout the winter. The edges may freeze, but the core will be hot. You can continue to turn the compost with a pitchfork throughout the winter. It just might not be as enjoyable in the cold. 🙂

A cold composting system will continue to decompose as the weather allows. Keep adding to your pile as you normally would, but be prepared for what to do if you reach capacity. Storing your scraps in the freezer is a good option!

What do you do with your compost in the winter?

You don’t need to do anything special to prepare or maintain your compost in the winter. You can continue on as you typically would, but know that the process may slow down.

Spring time, however, may require extra attention. Freezing temperatures break the cell walls of plant materials and speed up the breakdown process. This can lead to a stinkier pile. Turn it and add more browns to the pile.

Composting Services

Where can I drop off my compost?

Kompost Kids has a community drop off site in Riverwest. (Update: The Riverwest site is currently closed, but they have a new site in Milwaukee’s Garden District.) You could also drop off your compost with a neighbor! Find your neighbors composting at You could also use a paid pick up service to have scraps picked up from your home.

Check out Milwaukee area drop off and pick up services here!

Note: Composting as close to where you eat as possible is most sustainable. Organic waste is heavy. The further it is transported, the more emissions are produced.

What resources are available in Western Waukesha County?

Check if a pick up service is available in your area here.

If not, is there a small farmer near you? Using kitchen scraps to feed animals is a great option! It’s a couple steps before composting in the Food Recovery Hierarchy. A small farmer may also have a hot compost you can contribute to.

Are you ready to compost?! Do you have any other questions? Check out the How to Compost in Milwaukee Guide, or leave a comment here and I can help you out. 🙂