Troubleshooting Guide
Common Composting Mistakes and How to Fix Every One
Most compost problems come from two things: wrong ratio or wrong moisture. The rest come from not turning. Here is every common mistake and the exact fix.
Mistake 1: Too much nitrogen, not enough carbon
Symptom: Ammonia smell, wet and slimy pile.
Fix: Add dry browns: shredded cardboard, dry leaves, or straw. A 3:1 browns-to-greens ratio by volume is the target. Add browns generously, then turn the pile to mix.
Mistake 2: Too much carbon, not enough nitrogen
Symptom: Pile does not heat up. Decomposition is very slow. Material looks the same after months.
Fix: Add nitrogen-rich material: food scraps, coffee grounds, or fresh grass clippings. Water the pile if it is also dry. Turn to mix the new material throughout.
Mistake 3: Pile is too dry
Symptom: No heat, no activity, pile feels dusty.
Fix: Water the pile until it feels like a wrung-out sponge. A handful of compost should yield a few drops when squeezed. Cover with cardboard or a tarp to slow moisture loss in hot weather.
Mistake 4: Pile is too wet
Symptom: Sulfur or rotten-egg smell. No heat. Pile feels like a wet mat.
Fix: Add dry carbon material: cardboard, straw, or dry leaves. Turn the pile to expose wet interior material to air. Remove the cover if you are using one. Let it breathe.
Mistake 5: Pile is too small
Symptom: No heat at all. Decomposition is very slow even with correct ratio.
Fix: A pile needs at least 3x3x3 feet to heat up properly. Add more material, building the pile from all sides. Or combine two piles into one.
Mistake 6: Adding food scraps without covering them
Symptom: Pest activity, flies, smells.
Fix: Always bury food scraps 4-6 inches into the pile and cover with browns. Exposed food is an open invitation for pests. A covered tumbler composter eliminates this problem entirely.
Mistake 7: Adding meat, dairy, or cooked food to an outdoor pile
Symptom: Strong smell, pest digging, slow decomposition.
Fix: Remove what you can and bury the rest deep. For ongoing meat and dairy composting, use an electric composter like Lomi that handles those inputs without an outdoor pile.
Mistake 8: Not turning the pile
Symptom: Pile works very slowly. Anaerobic conditions in the center.
Fix: Turn the pile every 3-7 days. Even once a month is far better than never. Turning adds oxygen and redistributes heat and moisture. A tumbler makes turning a 10-second task.
The fastest way to fix a broken pile
If a pile has been sitting for months with no progress, do this in order:
- Turn the entire pile. Move outside material to the center and center material to the outside.
- Check moisture. Squeeze a handful. If no water comes out, water the pile thoroughly as you turn.
- Add greens if the pile is mostly browns: two buckets of food scraps or a bag of coffee grounds.
- Cover the pile loosely with cardboard to retain moisture.
- Turn again in 3-4 days and check for heat in the center.
A pile that was stalled for 6 months can restart and finish in 4-8 weeks with this approach.
When to switch to a tumbler
If managing an open pile consistently produces smells or pest problems, a sealed tumbler removes both issues. Tumblers block ground pests, retain moisture automatically, and make turning require almost no effort. Our tumbler guide covers the top picks by capacity and price.
Common questions
Why does my compost smell bad?
Two main causes: too much nitrogen without enough carbon (ammonia smell), or too little oxygen from not turning or being too wet (sulfur, rotten-egg smell). For ammonia smell, add dry cardboard or leaves. For sulfur smell, add dry material and turn the pile to add air.
Why are there flies in my compost?
Exposed food scraps. Always bury food scraps 4-6 inches deep and cover with a layer of browns. A tight-fitting tumbler eliminates fly access entirely. Black soldier flies are actually beneficial decomposers but can be off-putting. Fruit flies come from exposed sweet material near the surface.
Why is my compost not hot?
Three common causes: pile is too small (below 3x3x3 feet), not enough nitrogen, or too dry. Fix in that order: add more material, add food scraps or coffee grounds, and water if needed. A pile that is actively composting should reach 130-160 degrees in the center.
Can I add too much compost to a garden?
Yes, though it is hard to do with finished compost. Very large amounts can create nutrient imbalances, particularly in phosphorus. A 1-3 inch layer per season worked into the top 6 inches of soil is appropriate. More than 4 inches at once is usually unnecessary and can temporarily tie up soil nitrogen as it integrates.
Why are there pests in my compost bin?
Exposed food scraps, especially meat, dairy, or sweet fruit, attract rats, raccoons, and other animals. Remove these inputs and bury all food scraps under a thick layer of browns. A tumbler with a sealed body and elevated stand prevents almost all ground-dwelling pests.