How to fix common compost problems: smells, flies and slime

Learn how to diagnose and fix the eight most common compost problems, from rotten smells and slimy mush to fruit flies, rodents and a pile that will not heat up. It suits beginners with a home bin or heap who want to get their compost working again.

Why Your Compost Isn't Working: 8 Problems and Easy Fixes, by Compost or Not on YouTube. 3 min 14 s.

10 chapters. Tap a step to jump to it.Chapters from the creator
Video length
3 min 14 s
Time to do it
20 minutes
Difficulty
Easy
Steps
8

What you need

Steps

  1. Check the smell first. A rotten, sour smell means the pile is too wet and short of air. Turn it over with a fork and mix in dry brown material.

  2. If the pile will not heat up, add more green material such as grass clippings or fresh scraps. Turn it to mix everything and keep the pile about as damp as a wrung-out sponge.

  3. For slimy, soggy mush, stop adding wet scraps for a while. Fork in dry leaves or shredded cardboard and turn the pile every few days so air gets through.

  4. If the heap is dry and dusty, water it lightly while turning. Aim for the whole pile to feel moist but not dripping.

  5. To stop fruit flies and gnats, bury kitchen scraps under a layer of browns. Keep the lid on and avoid leaving exposed food on top.

  6. To keep out rodents and raccoons, do not add meat, dairy or cooked food. Use a lidded bin with a secure base or a closed tumbler.

  7. If weeds sprout from the compost, keep out seed heads and roots of perennial weeds. Hot-compost them separately or leave them out.

  8. Check whether the compost is finished. It should be dark, crumbly and smell earthy, with no recognisable food scraps left.

Tips and common mistakes

Keep a rough balance of two parts browns to one part greens to avoid most problems.

Turn the pile regularly so air reaches the centre and smells do not build up.

Never add meat, dairy or pet waste to a home bin if rodents are a concern.

Wear gloves when turning compost and wash your hands afterwards.

Questions

Why does my compost smell like rotten eggs?

The pile has gone anaerobic, usually because it is too wet and packed down. Turn it, add dry browns and keep it damp rather than soaked.

How long until my compost is ready?

It depends on the bin and how often you turn it. A hot pile can finish in a few months, while a cold heap may take a year or more.

Can I put citrus and onion in compost?

Yes, in small amounts. Bury them in the pile so flies and rodents are not attracted to the surface.

This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.

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