When to Bin or Sheet Compost

The two major types of composting methods are bin composting and sheet composting. When trying to decide which method to use, it mainly depends on what and when you want to plant and how much time and money you want to spend. Here are just some of the advantages and disadvantages.

You can bury organic matter directly in the soil. This method is known as sheet composting with incorporation.

1. Least labor expenditure since you handle the organic matter only once.

2. Ending NPK release is just as good as bin composting.

3. Almost 0% loss of nitrogen through ammonia evaporation.

4. Increased soil bio-activity allows nature to do the work for you.

Soil Food Web

5. Nutrient dense crops thrive under a high residue system. ( ie: turnip, kale, okra, etc.) They have the toughness to withstand the increased soil bio-activity as long as clean culture of crop residue is practiced in the fall.

6. Crops that do better with low nitrogen early in their growth cycle and then require high nitrogen later in their growth cycle tend to do well under a high residue system. (Squash, kale, collards, okra, etc.) These crops spend the first few months putting down roots and using potassium. Too much nitrogen early makes them leggy.

7. Helps feed mycorrhizal fungus during their saprophytic stage until the right roots come along.

1. Must wait at least two weeks or more before planting, depending on how much organic matter you work in, how much it has been partially pre-decomposed, and what you are going to plant.

2. If you use fresh manure, the USDA recommends a 90-120 day wait before consuming raw. If you work manure in by early December, you can harvest raw by early or late March.

3. Requires extra available space to bury organic matter in.

4. Increases the risk of introducing weed seeds into the garden.

5. Low nutrient crops (ie: lettuce, cucumber, etc.) tend not to thrive under a high residue system. They have little defense against insects and fungus.

6. Tomato and potato originated from Peru. They evolved in a dry low residue environment. They tend to have disease problems under a high residue regularly watered system.

University of Illinois - sheet composting

Soil and Health - sheet composting

ATTRA - sheet composting

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Or, you can use bin composting:

1. Can plant or side dress immediately without fear of burn or stunting.

2. May be the only appropriate method for omnivore manure, restaurant scraps, mushroom medium, kitchen scraps in small city areas, seedling trays, house plants, etc.

Humanure Handbook

3. Slow release spread out over several years is appropriate for fruit and nut trees / vines.

4. Can consume produce any time after the use of bin compost.

5. Reduces the risk of introducing weed seeds into the garden.

6. Low nutrient crops (ie: lettuce, cucumber, etc.) thrive better under a low residue system.

7. Tomato and potato originated from Peru. They evolved in a dry low residue environment. They tend perform better under a low residue system.

8. Crops that demand high levels of nutrients throughout the growing cycle perform best with bin compost. (bell peppers, broccoli, spinach, etc.)

9. Root crops where off flavors might be absorbed from continuing decomposition sometimes perform better under low residue. (carrot, parsnip, salsify, etc.) Thumbalina carrots and beets are exceptions since they ride above the soil.

10. Short cut to building up bacterial populations in a new garden.

1. Requires more labor since the material is handled at least several more times. People must work harder to make up for lower soil bio-activity.

2. May require extra expense to obtain proper materials to balance the materials you already have.

3. Slow release spread out over several years is not as appropriate for vegetables, legumes, or grains where a more complete cycling of nutrients within one growing season is desirable.

4. Bin composting is mainly bacterially dominated. It does little to encourage growth of beneficial fungus.

5. Study showing cost of nitrogen sources, with bin composting being more expensive than working some other forms of organic matter directly into the soil:

University of Vermont - cost of nitrogen sources

6. Study showing loss of nitrogen through evaporation of ammonia.

Washington State University - loss of nitrogen during bin composting

7. Nebraska University - 'Direct application of fresh manure with immediate incorporation is the best way to get the maximum amount of nutrients back to the field production environment.'

Nebrask University - organic agriculture

8. Extremely precise procedures and meticulous care can remove most pathogens. But even the professionals are having a hard time meeting EPA standards.

Food Safety News

9. ATTRA warns against the assumption that hot composted pig manure is safe.

ATTRA - safe use of manure

Since time and money are very important to most people, it is advisable to use sheet composting most of the time. It will require closer attention to timing and stringent assessment of weed seed potential. Bin composting has certain times when it is ideal, such as when growing crops that are the most demanding for full nutrient levels during their entire growth cycle, etc. It is odd that the most demanding crops often have either the most anti-nutrients or are among the most inefficient nutrient producers.