Soil Ingestion (also called Soil Digestion)

In-soil digestion modifies the Soil Incorporation method (i.e., burial of wastes) by introducing a container into the process. The presence of a container alleviates you from having to choose a new location, and also from having to dig a hole every time you dispose of wastes. It allows you to recapture the compost to use elsewhere if you choose to do so.

The Container
You can build or buy the bin. Many types and sizes of soil digesters are available through vendors.

A good way to build one is to use a plastic outdoor garbage can of a size appropriate for you with a "locking lid" that snaps shut tight. If you have a family or large dogs, you may want to use a full-size garbage can. If you live alone and don't cook much, you can use a plastic canister with a locking lid. The air-tight lid is the key.

Choose a location that is well-drained. For easy access, I know one gentleman who has a soil digester located next to the walk right outside his kitchen door. If there is any chance you will use this receptacle for cat or dog feces, adhere to the warnings regarding location, i.e., do not locate near a water source or crops for human consumption that could become contaminated.

Cut out the bottom of the can. Dig a hole deep enough to set the can down into it with only 1 foot (or less) in height of the can showing above ground. Fill dirt in tight around the outside of the can. The illustration to the right is the ingestor of my friend Bert Whitehead, compost expert, author, and teacher.

If you are building a raised bed, save yourself the trouble of all this digging. Before you put soil into the bed, set the can in the bed, then fill in around it. That's how I build mine with a smaller container than Bert's, and mine shows only about 1" above the ground.

In urban and suburban areas, the "locking lid" needs to close tightly, but probably does not actually need a lock on it. Forest Rangers compost their food scraps this way and, in order not to attract bears, etc. have to take the "locking" part of that description a bit more seriously. They not only lock the can itself with a padlock, they build a fence around it. Secure the lid in a way that is appropriate for your environment.

Using this System
To dispose compostable food wastes or pet feces, lift the lid, throw wastes in, replace the lid. If flies or odor becomes a problem, cover each deposit of food with a very thin layer of soil or sawdust.

How It Works
Because the lid on the can shuts tight, smell does not escape until you open the lid. This composting process is an anaerobic process, i.e., without oxygen, and that usually means smelly. When you open the can to throw food wastes in, it may smell bad while you have the lid off. I use this method of composting for food and pet wastes. The ones I have used and seen have not smelled bad if they were located in a well-drained area. If you locate it where it stays wet all the time, stand back when you lift off the lid.

Keeping the smell inside the can means animials are not attracted. However, if eggs of gnats or flies were on the materials you put into the ingestor, they may be hatched and flying around next time you take off the lid. I haven't had too many times when gnats were in there, and never flies. Since the lid is off only for a few minutes, I don't consider this a problem. They will die without air anyway. If they bother you, cover the wastes with a very thin layer of soil, sand or sawdust and they will die quicker because they have nothing to eat. Remember, though, that if you put soil, sand or sawdust in your digester, it will fill up much more rapidly. If you plan to do this, install a larger container than you think you need.

Harvesting (Optional)
Under these anaerobic conditions, it will take about a year for scraps to compost. It takes even longer to fill up. As wastes decompose, normal volume reduction occurs. In addition, because the bottom of the ingestor is open to the soil, earthworms can come and go as they please, taking the wastes with them as they go. If you have chosen a container of adequate size, it takes a long time to fill up. I installed a small container in 1998 and it isn't full yet, not even close. The larger your container, the longer it will be before you have to do the work to install a new digestor!

When the can fills up, you can leave the compost where it is, pull out the bin and move it to a new location. Or, you can leave the can in place, then scoop the compost out of the can to use elsewhere when you need it.

Because the wastes that are least decomposed will always be on top, it is not practical to harvest finished compost on the bottom as you go along. This is not a method for generating finished compost quickly for use elsewhere on your property. Unless you have a LOT of ingestors, it will not handle volumes of yard trash. However, it is a convenient and easy way to quickly dispose of wastes that can cause problems in the pile such as food, pet feces, and weed seeds.

Note added 2010:
Check out the Soil Ingestor article I wrote for CompostMania's LEARN section.

Online Stores
Compost Tea Brewer
Build a brewer with a bucket and less than $15 worth of components, and make aerated compost tea.
Composting the Holidays
Compost fall leaves, hay bales, holly wreaths, pine trees, etc. Compost pumpkins (food waste) in a compost pile.



  1. Soil Incorporation
  2. ** In-Soil Ingestion **
  3. Trench Composting
  4. Mulching
  5. Composting Toilets
  6. Compost Tea

Return to Home Page
Return to Compost Site Contents

Make Your Own Brewer
Brew Compost Tea at Home!

eBook $9.95
Download Now!

Return to Home Page  /   eBooks  /   Return to Compost Site Contents

Home Page URL:
Use of this web site constitutes acceptance of all terms in our Terms of Use.
Copyright - © 2003, Mary J. Tynes.