Compost Bin Layering Using Alfalfa Cubes - Late Summer - 2021
Over the weekend, I posted a couple of photos that showed the latest turn in our two-bin and one tumbler compost setup in our backyard. Since last Summer, I had one bin (the one on the right as you face it) in 'cooking' mode. That one has some pvc pipes installed for passive aeration and was (mostly) the right mix of greens and browns. The second bin (on the left) has been my storage, inactive bin. I almost everything in there that I had collected since last Fall. That means, once the bin on the right was full of the final grass and leaves combo from early Fall, I started to put in everything on the left.
In the post from a few days ago, I showed how I had emptied out the active bin and took the (mostly) finished compost and moved it to my tumbler for a final few months of cooking. My plan is use that compost come Spring time and will use the rest of the Summer and Fall to get it finished. I also took the rest of the (not quite finished) material from the active bin (the stuff on top) and piled it up in the storage bin on the left. That's where I left it - and mentioned that I was going to try to use a new (to me) natural accelerator (alfalfa cubes) and add a little bit more passive aeration to the active bin.
That brings us up to today's post. In the photos below, you'll see the the final state of the bins (full, once again on the right and empty on the left ready to start collecting Fall leaves) and how I got there.
First, let's talk about alfalfa cubes. I learned this tip from Erin the Impatient Gardener on her YouTube channel where she talks about the 'only thing she buys for her compost bin': alfalfa cubes. See the video embedded below:
Now...it turns out that the most common place to buy these big 40 or 50 pound bags of alfalfa cubes is from a feed store. Nat's Mom keeps horses, so of all the people I know, I figured she'd be at a feed store at some point. I asked her that if she comes across a bag of cubes to pick them up for me. Earlier this Summer, she dropped off this big green bag:
What do they look like? See below for the dried, clumped-together cubes. They have a smell. It isn't BAD, but it isn't GOOD, either. Something in-between.
I went about taking Erin's advice and putting about three dozen cubes into a five-gallon bucket and filling it up. I have a lot of leaves (browns) that make my bin to be pretty carbon-rich. That means that it isn't the right mix of things. The upside of that is that while it is moving pretty slow, I'm not getting the algae-stuff she's talking about that tends to happen when you go the other way with your mix.
After adding in a layer of the material from the storage bin (lots of leaves), I took the bucket (which was now a slurry of sorts) and dumped it in and spread out the wet alfalfa into a sort-of layer. Then, piled on even more of the material from the storage bin. I found big pockets of leaves from last Fall (especially the Oak leaves) that weren't broken down very much. I was deliberate in making that layer of leaves thin. Then, ANOTHER five-gallon bucket of alfalfa cubes that I soaked.
I ended up adding six five-gallon buckets of soaked alfalfa cubes - in layers that alternated between the mix of materials in the storage bin and a thin layer of alfalfa. Erin, in her video (embeded above and linked here) calls it 'alfalfa soup', is what you see in the photo below.