Odors are one of the most frequent but easily avoidable composting problems.
Rotten Odor - A putrid smell or rotten egg smell usually results from anaerobic conditions (i.e., excess moisture or compaction). To remedy, turn pile, add dry porous material (browns), and cover kitchen scraps.
Ammonia Odor - This smell usually means too much nitrogen (greens). To remedy, add high carbon material (browns), and turn the pile.
A low pile temperature could indicated that your compost pile is too small, too dry, has poor aeration, lacks nitrogen, or could be due to cold weather. To remedy, make the pile bigger or insulate sides, add water, turn the pile, and add greens or manure.
A high pile temperature usually means the pile is too large and suffers from insufficient ventilation. To remedy, reduce pile size and turn.
If your compost pile is subject to pests, such as raccoons, rats, or insects, this could be related to the presence of meat scraps or fatty food waste and rotten odors in your pile. To remedy:
Remove meats and fatty foods, cover with sawdust or leaves, and turn the pile.
Compost in an animal-proof bin (i.e., a bin with a cover) that has wire mesh sides and floor (1/4 inch – 1/2 inch openings).
Use worm composting (vermicomposting) for food scraps.