DIY Passive Compost Aeration - Perforated PVC Pipe Inserted Horizontally - May 2020
Number 6 (#6) on my 2020 To-Do list in the garden this year was to add some passive aeration mechanism in our compost bin setup in the backyard. I have a three-bin setup (one active bin, one carbon storage bin, one nitrogen storage bin) and a 50 gallon tumbler. Last Fall, the active bin (on the left) was about half-full and I was storing the excess leaves in the carbon storage bin (middle).
Earlier this year, I posted some discussion about various passive compost aeration techniques - including one design with vertically installed pvc pipes and another with horizontally inserted perforated pipes.
After poking around on the Web, I decided to go with 10' sections of 2" perforated PVC pipe inserted horizontally in the pile. My bins are 3' x 3', so I cut down 6 40" sections.
Then, I grabbed my garden fork and started to dig out the active bin of compost to get the volume low enough to install the pipes at a level that would make them work well. Here, below, is the left (active) bin mostly empty with the partially-composted material in my garden cart and the middle, carbon storage bin.
I started by taking a 1/2" drill bit and drilled holes on all sides of the pipe about every 4" to 6" apart.
Then cut them down to 40" each - to make the most of the 10' long pipes.
I dug low enough to have about 8" of compost/material from the ground and then laid three of the perforated pipes in and piled material on top to get them stable. If you look closely at the pipes, you'll see the holes that I drilled:
I used the fork to pile even more material on top of the pile, and about 8-10" up, I stuck in three more pipes. More material on top of the second row of pipes and then I ran out of steam. I also want to get a bag of Compost Starter from the hardware store and add it to the pile to help accelerate the 'cooking'. Once I get that starter applied, I'll add more of the existing material on top.
In the next few days, I'll add that Compost Starter and then pile back on all the excess material in the active bin by layering on some carbons and nitrogen.
My plan is to then snip a few of the pieces of fencing to allow for the pipes - which are 4" longer than the bin would allow - to stick out front of the bin.
I'm considering this item (#6) crossed off my list.