If you’re short on outdoor space but hate throwing away peelings and coffee grounds, indoor composting is a brilliant way to cut waste and feed your plants at the same time. With the right container and method, you can compost in a flat, small house, or even a single room without bad smells or mess.

In this indoor composting guide, you’ll learn the best methods for small spaces, how to keep things odour-free, and how to use finished compost for houseplants and containers. If you’re planning to refresh tired soil afterwards, you might also like How to Reuse Potting Soil Safely for Indoor Plants.

What Is Indoor Composting?

Indoor composting is simply composting on a smaller, more controlled scale so you can do it inside – in a kitchen, utility room, cupboard, or balcony corner – without creating a mess or attracting pests.

Instead of a big outdoor heap, you use a compact system that:

• Holds food scraps neatly

• Keeps odours under control

• Breaks materials down into a soil-like mix or liquid feed

• Fits into your normal indoor routine

Most indoor composting focuses on kitchen scraps (veg peelings, coffee grounds, tea, eggshells) plus small amounts of paper or cardboard. Meat, fish and large amounts of cooked food are usually avoided, unless you’re using a tightly sealed system like bokashi.

Best Indoor Composting Methods for Small Spaces

There’s no single “right” way to start indoor composting. The best method depends on your space, how much waste you produce, and how hands-on you want to be.

Kitchen Caddy + Outdoor or Collection

Even if you can’t do full composting indoors, a simple kitchen caddy helps you collect scraps cleanly for:

• An outdoor compost bin (if you share a garden or have access to one)

• A community compost, allotment or neighbour’s compost heap

• Local food waste collection services

A kitchen compost caddy with charcoal filter keeps smells down and makes it easy to empty scraps where they’re needed without constantly walking outside.

Worm Bins (Vermicomposting)

Worm bins are one of the most popular ways to do true indoor composting in small homes. Special composting worms (usually red wigglers) break down your kitchen scraps into rich worm castings that plants love.

Pros:

• Produces high-quality, nutrient-rich compost

• Can be kept in cupboards, hallways or utility rooms

• Relatively low odour if managed correctly

Cons:

• Worms don’t like big temperature swings or being overfed

• You need to avoid very spicy, salty or oily food waste

• Takes a little learning at the start

A compact indoor worm composting bin with stacking trays makes it easier to manage food levels and harvest finished compost without disturbing the whole system.

Bokashi Bins

Bokashi is a fermentation-based method where you layer food scraps with a special bran inoculated with beneficial microbes.

• Works well for almost all food types, including small amounts of meat and cooked leftovers

• Sealed bins keep smells very low when used correctly

• Produces a fermented pre-compost and a liquid that can be diluted and used as fertiliser

You usually follow up bokashi by:

• Burying the fermented material in a planter or raised bed

• Adding it to a worm bin or outdoor heap to finish breaking down

A bokashi compost bin starter kit is a straightforward way to get everything you need – bucket, tap, and bran – to start fermenting kitchen scraps indoors.

Setting Up Your Indoor Composting System

Whatever method you choose, a few basic principles keep things clean, efficient and beginner-friendly.

Choose a Good Location

Look for a spot that is:

• Easy to access while you cook (to encourage you to use it)

• Out of direct sun so it doesn’t overheat

• Away from radiators or very cold draughts

• On a washable surface or mat in case of spills

Balance Greens and Browns

Indoor composting still relies on the same basic balance as outdoor composting:

• Greens: Fresh scraps like veg peelings, coffee grounds, tea bags, fruit waste

• Browns: Shredded cardboard, paper, dry leaves, paper egg boxes

A good rule of thumb is to add a small handful of browns each time you add a batch of greens. This helps:

• Absorb moisture

• Reduce smells

• Keep materials fluffy so air can move through them

Resources like Royal Horticultural Society advice on home composting can help you fine-tune ratios of greens and browns and troubleshoot any tricky issues.

Keep It Airy (When Needed)

Traditional composting and worm bins both need some air:

• Gently fluff or stir the top layer now and then (unless it’s a sealed bokashi bin)

• Avoid packing waste down tightly

• Don’t let the container become a wet, compacted lump

How to Use Indoor Compost for Houseplants and Containers

Once your system has been running for a while, you’ll start to get finished compost or worm castings. This should look dark, crumbly and earthy, with no obvious chunks of fresh food left.

Mixing Compost into Potting Soil

For houseplants and containers:

• Mix up to 25–30% compost with fresh potting mix for hungry plants

• Use a lighter ratio (10–20%) for more sensitive species

• Avoid using pure compost on its own – it’s too rich and may compact

Top Dressing Pots

You can also use compost as a top dressing:

• Spread a 1–2cm layer on the surface of the compost in pots

• Gently work it into the top layer with your fingers or a small fork

• Water as normal so nutrients wash down into the root zone

Liquid Feed from Worm Bins or Bokashi

Many worm bins and bokashi systems produce a liquid that can be used as fertiliser:

• Always dilute according to the instructions (it’s very concentrated)

• Apply to moist soil, not bone-dry pots

• Use occasionally during the growing season rather than every single watering

Troubleshooting Indoor Composting Problems

Even well-run systems sometimes hit a bump. Here are some common issues and simple fixes.

It Smells Bad

Bad smells usually mean too many wet “greens” and not enough dry “browns”, or not enough air.

• Add extra shredded cardboard or paper

• Stir gently (for worm bins and open systems)

• Check for puddles or standing liquid and drain if needed

Fruit Flies and Gnats

• Always cover fresh food scraps with a layer of browns or finished compost

• Keep lids closed properly

• Wipe rims and edges so residue doesn’t attract flies

Mould on the Surface

A light white or fluffy mould on browns is often normal. Heavy, slimy mould with a strong smell means things are too wet.

• Add extra dry material

• Ease off on very wet scraps for a while

• Stir gently to introduce more air

It’s Not Breaking Down

If materials just seem to sit there:

• Check it’s warm enough – very cold rooms slow composting

• Chop scraps smaller before adding

• Make sure there’s enough moisture (slightly damp like a wrung-out sponge)

FAQs About Indoor Composting

Does indoor composting smell?

A well-managed indoor compost system should smell earthy, not rotten. If you notice strong odours, it usually means there’s too much wet food waste and not enough dry material or air. Adjusting the balance and giving things a gentle stir usually solves it.

Can I compost meat and dairy indoors?

Most basic systems (like worm bins) work best with plant-based scraps only. Bokashi bins can handle small amounts of meat and dairy, but you still need to follow the method carefully and let the fermented material finish breaking down in soil or another compost system afterwards.

How long does indoor composting take?

It varies by method and conditions. Worm bins can produce usable compost in a few months once established. Bokashi fermentation takes a couple of weeks per bucket, followed by soil integration. Kitchen caddies are just collection points and don’t do full composting on their own.

Is indoor composting safe in a flat?

Yes, as long as containers are well maintained, lids are secure and you manage moisture and airflow sensibly. Many people keep worm bins or bokashi buckets in kitchens, utility rooms or cupboards without issues.

Can I use indoor compost on all houseplants?

Most houseplants enjoy a small amount of compost mixed into their potting soil or added as a top dressing, but avoid overdoing it on very low-feed plants or those sensitive to rich soil. When in doubt, start with a weaker mix and see how your plant responds.

Related Articles

• Perfect Watering Schedule for Indoor Plants | Easy Care Routine

• How to Use a Soil Moisture Meter for Indoor Plants 

Final Thoughts on Indoor Composting

Indoor composting is one of those habits that feels a bit intimidating at first, then quickly becomes second nature. Once your system is set up and you understand the basics of greens, browns, moisture and air, you’ll wonder why you ever threw all that goodness away.

Whether you choose a simple kitchen caddy, a worm bin or a bokashi setup, you’ll be turning everyday scraps into something genuinely useful for your houseplants and containers. Over time, that means richer soil, stronger plants and less waste leaving your home.