Composting is a fantastic way to reduce waste, enrich your garden soil, and contribute to a more sustainable lifestyle. However, the composting process isn't always smooth sailing. Sometimes things go wrong – your compost might smell bad, decompose too slowly, or attract unwanted pests. This guide will help you troubleshoot common composting problems and get your compost back on track.
Understanding the Basics of Composting
Before diving into troubleshooting, it's important to understand the fundamental principles of successful composting. Composting relies on a balance of "greens" (nitrogen-rich materials), "browns" (carbon-rich materials), air, and moisture. Microorganisms, like bacteria and fungi, break down organic matter in the pile. When these elements are out of balance, problems arise.
- Greens: These provide nitrogen, which is essential for microbial activity. Examples include grass clippings, vegetable scraps, fruit peels, coffee grounds, and manure.
- Browns: These provide carbon, which provides energy for the microbes and adds bulk to the compost. Examples include dried leaves, straw, shredded newspaper, cardboard, and wood chips.
- Air: Microorganisms need oxygen to thrive. Insufficient aeration leads to anaerobic conditions, which cause foul odors and slow decomposition.
- Moisture: A compost pile needs to be damp, like a wrung-out sponge. Too dry, and the microbes will become inactive; too wet, and the pile will become anaerobic.
Problem #1: Foul Odors
A properly functioning compost pile should have a mild, earthy smell. Foul odors are a sign that something is wrong, usually an imbalance of air and/or moisture.
Rotten Egg Smell (Hydrogen Sulfide)
A rotten egg smell indicates anaerobic conditions – a lack of oxygen. This usually happens when the pile is too wet and compacted.
Solutions:
- Turn the pile: Use a pitchfork or compost aerator to introduce air into the pile. Turn it completely, mixing the materials thoroughly.
- Add bulky browns: Incorporate dry, carbon-rich materials like shredded newspaper, straw, or wood chips to absorb excess moisture and create air pockets.
- Improve drainage: If your compost bin is sitting on a surface that doesn't drain well, move it to a better location or add a layer of gravel underneath.
- Avoid compacting the pile: Don't compress the compost pile when adding materials.
Ammonia Smell
An ammonia smell indicates an excess of nitrogen (greens). This usually happens when you add too many nitrogen-rich materials without enough carbon.
Solutions:
- Add more browns: Incorporate plenty of dry, carbon-rich materials to balance the nitrogen. A good ratio is generally 2:1 or 3:1 browns to greens by volume.
- Turn the pile: Turning will help release some of the excess ammonia gas.
General Putrid Smell
A general putrid smell can be caused by a variety of factors, including anaerobic conditions, the presence of meat or dairy products, or an excess of moisture.
Solutions:
- Remove prohibited items: Never compost meat, dairy, oily foods, or pet waste, as these can attract pests and cause unpleasant odors.
- Turn the pile: Aerate the pile to reduce anaerobic conditions.
- Add more browns: Balance the moisture and nitrogen levels with carbon-rich materials.
Problem #2: Slow Decomposition
If your compost isn't breaking down as quickly as you expect, it could be due to several factors, including lack of moisture, lack of nitrogen, insufficient aeration, or cold temperatures.
Pile is Too Dry
Microorganisms need moisture to thrive. If the pile is too dry, they will become inactive, and decomposition will slow down.
Solutions:
- Water the pile: Moisten the compost pile until it's damp, like a wrung-out sponge. Use a hose or watering can.
- Cover the pile: A lid or tarp can help retain moisture, especially in hot, dry weather.
- Add moisture-retentive materials: Incorporate materials like shredded paper or coconut coir, which hold water well.
Pile is Too Cold
Microorganisms are more active at warmer temperatures. In cold weather, decomposition will naturally slow down.
Solutions:
- Insulate the pile: Wrap the compost bin with insulation or move it to a sheltered location.
- Increase the pile size: Larger piles retain heat better. A minimum size of 3 feet x 3 feet x 3 feet is recommended for hot composting (rapid decomposition).
- Add hot compost activators: Materials like manure or comfrey leaves can help generate heat in the pile.
Lack of Nitrogen
Nitrogen is essential for microbial activity. If your compost pile is primarily composed of browns, decomposition will be slow.
Solutions:
- Add greens: Incorporate nitrogen-rich materials like grass clippings, vegetable scraps, or coffee grounds.
- Use a compost activator: Commercial compost activators contain nitrogen and other nutrients to boost microbial activity.
- Add manure: Manure is a great source of nitrogen and other beneficial nutrients.
Insufficient Aeration
Microorganisms need oxygen to break down organic matter. If the pile is compacted and lacks air, decomposition will slow down.
Solutions:
- Turn the pile: Regularly turn the pile to introduce air.
- Add bulky materials: Incorporate materials like straw or wood chips to create air pockets.
- Use a compost aerator: A compost aerator is a tool specifically designed to aerate compost piles.
Material is Too Large
Large pieces of organic matter take longer to break down. The smaller the pieces, the faster the decomposition.
Solutions:
- Chop or shred materials: Cut up vegetable scraps, shred leaves, and break down cardboard into smaller pieces before adding them to the compost pile.
Problem #3: Pests in the Compost
Compost piles can attract a variety of pests, including flies, fruit flies, rodents, and other insects. While some pests are harmless, others can be a nuisance or even a health hazard.
Fruit Flies
Fruit flies are attracted to ripe and decaying fruits and vegetables.
Solutions:
- Bury food scraps: Cover food scraps with a layer of browns to prevent fruit flies from accessing them.
- Use a closed compost bin: A bin with a tight-fitting lid will prevent fruit flies from entering.
- Clean the compost bin: Regularly clean the bin to remove any food residue that might attract fruit flies.
- Vinegar Trap: Place a small dish of apple cider vinegar near the compost bin. Cover the dish with plastic wrap and poke small holes in the wrap. The fruit flies will be attracted to the vinegar and get trapped.
Flies
Flies are attracted to decaying organic matter.
Solutions:
- Bury food scraps: Cover food scraps with a layer of browns to prevent flies from accessing them.
- Maintain proper moisture levels: A compost pile that is too wet can attract flies. Add more browns to absorb excess moisture.
- Turn the pile: Turning the pile will disrupt the flies' breeding cycle.
- Use a fly trap: Hang fly traps near the compost bin.
Rodents
Rodents, such as rats and mice, are attracted to food scraps and warm, sheltered environments.
Solutions:
- Do not compost meat, dairy, or oily foods: These items are particularly attractive to rodents.
- Use a rodent-proof compost bin: A bin made of sturdy materials with a tight-fitting lid and a solid bottom will prevent rodents from entering.
- Locate the compost bin away from buildings: Keep the bin at least 10 feet away from your house or other structures.
- Clean up spilled food: Regularly clean up any food scraps that have spilled around the compost bin.
Ants
Ants can indicate that your compost pile is too dry.
Solutions:
- Water the pile: Add water to moisten the compost, making it less attractive to ants.
- Turn the pile: Disturbing the ant colony can encourage them to relocate.
Problem #4: Weeds Growing in the Compost
Weed seeds can survive the composting process if the pile doesn't reach high enough temperatures. These seeds can then sprout in your garden when you use the compost.
Solutions:
- Hot Composting: Maintain a hot compost pile (130-160°F) to kill weed seeds. This requires a proper balance of greens and browns, adequate moisture, and frequent turning.
- Avoid composting weeds with seeds: If you're not hot composting, avoid adding weeds that have already gone to seed.
- Solarize the compost: Spread the finished compost on a black tarp in the sun for several weeks to kill any remaining weed seeds.
Problem #5: Compost is Too Acidic or Alkaline
The ideal pH for compost is slightly acidic to neutral (around 6-7). Extremely acidic or alkaline compost can inhibit plant growth.
Solutions:
- Test the pH: Use a soil pH meter or test kit to determine the pH of your compost.
- If too acidic: Add lime or wood ash to raise the pH.
- If too alkaline: Add sulfur or acidic materials like pine needles to lower the pH.
- Balance the Ingredients: Generally, a good balance of greens and browns will help maintain a neutral pH.
Conclusion: Mastering the Art of Composting
Composting is a dynamic process that requires attention and adjustments. By understanding the basic principles of composting and troubleshooting common problems, you can create nutrient-rich compost that will benefit your garden and the environment. Don't be discouraged by setbacks – composting is a learning experience. Observe your compost pile regularly, make adjustments as needed, and you'll soon be a composting pro. As a next step, consider researching vermicomposting (composting with worms) for another efficient way to turn waste into valuable garden amendment. Happy composting!
References:
- Rynk, R., et al. (1992). On-Farm Composting Handbook. Northeast Regional Agricultural Engineering Service.
- The Composting Council Research & Education Foundation: https://www.compostfoundation.org/