Last year, I cut down a tree and chopped it into little bits, and I ended up with a giant pile of wood chips. While I could have tossed them around my garden as a bit of decorative mulch, I wanted to break them down and use them as compost instead – and I didn’t want to wait around for years to make it happen.
So how do you compost wood chips fast? The trick is to break them up as small as possible and then create the right balance between green and brown matter in your compost pile. That means having two parts green matter to one part brown matter. You also want to keep the pile warm, wet, and turn it often.
Of course, there’s more to it than just building up a healthy compost pile and hoping for the best. You can give the process a big boost if the chips aren’t breaking down quickly enough, and there’s a tried-and-true wood compost-building technique that you can take advantage of to really speed things up.
How to Compost Wood Chips Fast
The first thing you need to do to break down wood chips as fast as possible is to select the right location in your garden. Find a spot that gets at least 6 hours of sun a day. You also want it several feet away from any buildings.
Next, break the pieces down as small as you can. If you have 6-inch long pieces of wood, they’re going to take years to compost fully, no matter how hard you try. Either break larger pieces down using a wood chipper or use those larger pieces as kindling for your fire.
Next, you need the right mix of brown to green matter. You’ll hear this referred to as the carbon to nitrogen ratio. You’re shooting for a ratio of 30 parts carbon to 1 part nitrogen. Note that this is the chemical ratio that you’re looking for – not the volume. A 30:1 chemical ratio translates to about 2 parts carbon to 1 part nitrogen.
Green matter makes up the carbon in your pile, and brown matter – that’s the wood chips – make up the nitrogen.
In the real world, this means if you have one wheel-barrow full of wood chips, you’re going to need two wheel-barrows full of grass clippings, fresh leaves, fruit waste, and weeds. If you don’t have this exact mix, don’t worry. Compost piles are relatively forgiving. Just keep in mind that the closer you get to this ideal ratio, the faster your compost will decompose.
So what makes up green matter? Anything wet or recently growing is green matter, regardless of the color. So coffee grounds, food scraps, plant trimmings, grass clippings, eggshells, animal manures, seaweed, weeds, and tea bags are all green waste.
In addition to wood chips, dry leaves, pine needles, straw, sawdust, corn stalks, paper, and cardboard are all considered brown matter.
After you tackle the first steps, it’s time to master the moisture level. You need to have the right amount of water in your pile to keep it happy. You want the moisture level to be anywhere between 40-60 percent. You can buy a meter to test this, but you can also just give your compost a squeeze.
Take a scoop of compost and press it in your hand. If it feels like a wrung-out sponge, it’s probably good to go. If it’s slimy or smells bad, or if more than a few drops of water drip out, it’s too wet. If it crumbles easily and doesn’t stick together at all, it’s too dry.
Once you have the combination and moisture mastered, be sure to turn your pile using a pitchfork or shovel every few weeks.
Composting Wood Chips with Urea
If you have a lot more wood than you have green matter, you can bring in urea to help make your pile decompose faster. Urea is called a compost activator, and you can buy it at most gardening stores, or online here.
You can also use urine – human, or otherwise – if you’re feeling adventurous. You need about 5 ounces per 4-cubic feet of compost.
Sprinkle urea once each month onto the top of your compost. Be careful not to use too much, because urea can cause your pile to combust.
Instead of urea, you can sprinkle nitrogen-heavy fertilizer over the pile to hurry things up, but this won’t work quite as fast. The good news is, there’s less risk of combustion.
Add Fungus to Speed Up Wood Decomposition
Fungus is a natural way to speed up wood decomposition. Add an inoculant to your pile, and don’t turn the pile as you would normally. This allows the fungus to work its way through the compost.
You can also add a fungal-dominated compost tea every week to your compost pile.
Make a Jean Pain Style Compost Pile
If you want to speed things up even more, you can use the techniques established by Jean Pain to create a fast-acting compost pile primarily made up of brown material. Pain created a system that allowed him to heat his water using wood chip compost, but you can also use the same technique to encourage blistering fast decomposition.
Pain recommends starting by chipping the wood as small as possible. Then, create a pile of chips 5-feet tall by 7-feet wide. Wet the pile as you build it. Once you’ve reached the right size, cover the pile with an inch layer of leaves, soil, or compost. Cover the entire thing with a tarp or lots of pine boughs to keep it warm.
You don’t need to turn it, water it, or add anything to it, just let the pile sit until it’s ready. You can sprinkle fungal-based compost tea on top of the compost now and then, but don’t add urea or fertilizer.
Within three months, you should have a mulch. Within six months, you’ll have rich humus to add to your garden.