Written by Mary Johnson

Every gardener knows that a surefire way to make your veggie garden pop off is by adding compost. By using food scraps, yard waste, heat, water, and time, anyone can make their own nutrient-rich soil at home. But so many people are intimidated by making their own compost. We’ve heard all the arguments - it’s too much work; I don’t want food scraps in my yard; I’m worried about pests. Fear not! We are here with a great solution for folks who want to reap all the benefits of a home compost pile, without any of the hassle.

Enter: in-ground composting! In-ground composting is exactly what it sounds like: burying an enclosing compost pile directly into your garden. By burying food scraps, yard waste, and other organic materials in the ground, you can create a natural composting system right next to your veggie plants that requires very little maintenance and produces high-quality, nutrient-rich soil for your garden.

What are the benefits of composting?

• Reduces waste: Composting diverts organic waste from landfills by using food scraps from your kitchen, plant waste from your yard, raked leaves, and more!  By putting these materials into a compost pile rather than the trash can, we can reduce the amount of methane and other greenhouse gas emissions that contribute to climate change.
• Improves soil health: Compost improves soil structure, makes the soil more fertile, and increases soil's ability to hold water. Healthier soil means less need for added fertilizers, and lower risk of pest infestation.
• Saves money: Because compost improves soil health, using compost can save money by decreasing the amount of fertilizers and soil amendments you need to buy.
• Supports biodiversity: Composting at home can attract beneficial insects and microorganisms that help break down organic matter and support healthy soil. A diverse ecosystem in your garden means higher levels of biodiversity for the greater ecosystem around you!

What are the benefits of in-ground composting?

• Low maintenance: Once it’s set up, you’re good to go! No additional labor required.
• Efficient: The basic structure of an in-ground composter is a porous divider (like hardware cloth). This allows for organisms in the soil to access the organic material and convert it to nutrient-rich soil, much more quickly than would happen above ground. 
• Inexpensive: It doesn't cost much to start in-ground composting! If you're going for a DIY route (pictures and instructions below), the materials will cost you about $15. Pre-made bins run between $100 and $200. That might sound expensive, but when you consider that you won’t have to buy any additional compost for your garden, or do the work of spreading it around, it’s a great deal! 

What’s the difference between traditional composting and in-ground composting?

• Unlike compost piles or tumblers, in-ground composting does not require "turning", or moving the pile around to stimulate decomposition.
• Above-ground composting requires moisture management in order to support the decomposition process. In-ground compost bins get all of their moisture from your regular watering of your garden.
• In other gardens, we might recommend adding some compost around the base of the plants a couple of times during a growing season. With in-ground compost, there’s no need to add any additional compost to your garden. The porous structure allows nutrients to seep directly into the soil over time. 

We recently had a chance to make an in-ground compost for out garden at the SEED School: check it out below!

Here's what our DIY in-ground compost bin looks like after assembly, before installing it into the garden.

We helped the students select the perfect location within their garden bed. They dug a big hole, and put the bin inside...

Then, they filled the bin with organic materials. The student on the left has some “brown” material, and the student on the right has “green” material. (To learn more about what that means, you can check out this graphic.)

…and Voila! A beautiful and compact way to passively add nutrients to the garden.

How can I make my own in-ground compost bin?

Making an in-ground compost like the one at the SEED School garden is so easy!

Materials: (you should be able get these at any hardware store)

• Hardware cloth
• This is the metal grid that serves as the cylinder for the compost bin. You can pick it up at the hardware store by the roll, or ask around to see if you can take a small bit from your neighbor. If you have a standard 4'x8' raised bed, a 3'x5' piece is a good size to start with.

• A lid: 
• Any type of firm circular piece that can cover the top of the bin. Garbage can lids and  plastic bin lids (like from those five-gallon buckets) work great. Personally, we love using metal trash can lids for this type of project because of their classic, vintage feel…and it low-key looks like Oscar the Grouch is hiding in the garden. If you wanted to get artsy, you could even paint your lid!
• One thing to keep in mind: if you live in an area with pests, it might be helpful to secure your lid with a bungee cord or by putting something heavy (like a garden paver) on top of it, so no critters get in there.
• Zip ties

Instructions:

1. Decide on the best location for your bin. It should be in a central spot in your garden. 
2. Roll a piece of hardware cloth into a cylinder. The height of the cylinder should either be flush with your garden or sticking up just a little bit. Make sure the diameter of the cylinder fits snugly underneath your lid.
3. Use zip ties to secure the cylinder.
4. Dig a hole in your garden big enough to fit the bin, and insert the bin into the hole.
5. Add layers of brown (leaves, straw, mulch) and green (food scraps, organic garden trimmings) materials until the bin is full.
6. Secure the lid and you are done!

This is just one way to make an in-ground compost bin. There are lots of different style out there. Don't be afraid to get crafty!

What if I don’t want to make my own?

Like the idea of in-ground compost but don’t want to spend the time or energy making your own? We recommend a couple of options:

1. Our favorite in-ground composter company is called Subpod. They make a duo in-ground compost system and worm farm that is well designed and super functional. The worms speed up the process of converting organic material into compost. If you’re looking for a way to make compost at home fast, the Subpod is a great option. Their website has a lot of helpful information about vermicomposting, microbes, and composting in general. They are currently having a 40% sale that ends April 30, so get on it!
2. We can build one for you! Our gardeners have the materials, expertise, and passion to create, deliver, and install an in-ground composter that looks similar to the one featured in the pictures above. Because in-ground composters deliver nutrients directly to the adjacent soil, selecting a location for your composter is a crucial part of the process. We’ll use our expertise to analyze your garden, select the best location, and install a compost bin . Alternatively, if you want to buy a Subpod or another pre-made model, we can install it for you.