Using Blood and Other Organic Materials in Your Compost

A Comprehensive Guide to Adding Blood, Bone, and Other Animal Products to Your Compost Pile

Composting is a wonderful way to recycle your food scraps, yard waste, and other organic materials into a rich fertilizer for your garden. However, many composters have questions about adding certain items like blood, bones, and animal products to their compost piles. This article provides a detailed overview of how to safely and effectively compost blood meal, bone meal, meat, and other animal-based products.

Can You Add Blood to Your Compost Pile?

Blood meal and dried blood can be successfully composted, but care must be taken to avoid attracting pests. Here are some tips:

• Hot composting is ideal, as the high internal temperatures kill pathogens. Maintain temperatures between 130-150°F.

• Bury any added blood in the center of the pile, mixed thoroughly with carbon-rich browns. Avoid surface applications.

• Freeze blood before adding to compost for added safety. Allow it to fully thaw and incorporate into pile.

• Monitor for any pest activity. Rats, flies, and other scavengers may be attracted to the blood.

• Aged or composted blood of at least one year old is safest, as pathogens die off over time.

What About Bone Meal and Other Animal Products?

• Bone meal, fish meal, blood meal, and other animal byproducts can be excellent compost boosters when used properly.

• They provide a quick nitrogen source to balance carbon-heavy materials like leaves, straw, or sawdust.

• The optimal carbon-to-nitrogen ratio for active composting is 25-30:1. Animal meals help achieve this.

• Start with thin layers sprinkled lightly over browns. Too much may burn plants if compost isn't aged sufficiently.

• Like blood, incorporate fully into the center of the pile. Avoid heavy surface applications.

Can You Put Meat, Bones, and Fat in Compost?

Meat, bones, and fatty food scraps require extra precautions:

• Cooked or raw meat and bones can harbor harmful bacteria and pathogens. Never apply to soil surface.

• Bury deep in the hot center of the pile. Very high temperatures are needed to break down fat and kill bacteria.

• Chop or shred meat, bones, and fat into small pieces before composting. This allows thorough decomposition.

• Limit meat to small amounts, avoiding large volumes. Monitor for odors and scavengers.

• Fully aged compost with no recognizable meat bits is safe to apply in gardens. Sieve finished compost to remove bone fragments if needed.

Other Tips for Safe and Effective Composting

• Maintain aerobic conditions. Turn and mix compost regularly to prevent anaerobic pockets where pathogens can survive.

• Use compost activators like alfalfa, manure, or nitrogen fertilizers to ensure a hot, active pile.

• Add composted manure, old compost, or garden soil to introduce beneficial microbes.

• Shred or chip animal products, meat, and bones to speed decomposition.

• Follow proper curing and aging timelines before using animal-product composts on edible gardens.

Troubleshooting Problems

Odor- Insufficient oxygen, excess nitrogen, or too much meat/fat. Turn the pile and add carbon-rich browns like sawdust or straw.

Pests- Try traps, deterrents, or barriers for persistent pests attracted to compost. Eliminate meat and animal products if issues continue.

Slow decomposition- Mix in nitrogen fertilizers or meals. Add moisture if pile is too dry. Turn and aerate the pile.

Ammonia smell- Too much green nitrogen-rich material. Add more carbon-rich browns until ammonia smell dissipates.

Frequently Asked Questions About Composting Animal Products

Is it safe to use composted blood as fertilizer in my vegetable garden?

Composted blood that has been aged for at least one year is generally safe to apply to gardens. Further heating compost to at least 130°F ensures pathogen removal. Always wear gloves when handling.

How much bone meal can I put in my compost pile?

A thin sprinkling of 1-2 cups of bone meal per cubic foot of compost is a good rule of thumb. Excess bone meal can overwhelm the carbon balance. Monitor temperatures and amend as needed.

What is the best way to compost meat and fat trimmings?

Chop or shred meat, fat, and bones into small pieces first. Bury deep in the center of a hot active pile. Limit meat to 2-3% of total pile volume. Turn pile frequently and monitor for odor issues.

Can I put butcher waste like blood, bones, and meat trimmings in my backyard compost bin?

It's not recommended for small-scale composting. Very high temperatures are required to break down fat, blood, and kill pathogens. Municipal or commercial compost facilities are better equipped.

How long should I avoid planting in soil amended with animal product compost?

Wait 3-6 months after applying animal product composts before planting edibles. Monitor temperatures to ensure compost reached 130-150°F for pathogen removal. Test compost maturity before planting sensitive crops.

What precautions should I take when composting human waste or pet waste?

Do not compost pet waste or unprocessed human feces, as these can transmit harmful parasites and disease. Composting toilets require proper operation and maintenance for safety. Follow all guidelines carefully if composting human waste.

By understanding the opportunities and limitations for adding blood, bones, and animal products to compost, you can safely recycle these nutrient-rich materials into a high-quality growing medium for your garden! Monitor and maintain proper composting conditions for a successful end product.