The hot stuff
I'm bringing home spent coffee grains from local cafes, mumbling about carbon nitrogen ratios and the autumn rains have subsided somewhat.
Must be time to build a compost.
The end result of composting is humus. Humus is a soil conditioner, soil improver, water saver, microbe habitat and is 'plan available' food for your garden.
I like my compost 'hot'. The volume and ratios result in a heated environment which hastens the composting process and gets humus into my garden faster than a smaller, slower, add-it-as-you-go type compost. And, as it's winter, our ducks are getting most of our food scraps. With a hot compost, ideally, we're looking for a carbon nitrogen ratio of 25:1. The nitrogen provides the proteins for the microbes to build their bodies so they can munch on the carbon materials and break them down into humus - the process of composting. Carbon materials are characteristically brown and dry. Think straw, paper, woodchips and sawdust. Nitrogen materials are generally green and fresh. Think green leafy material, fresh grass clippings, animal manure, blood and bone and azola.
I build my compost like a lasagne - a big 1 cubic metre lasagne of decayed organic matter containing gazillions of beneficial soil critters working fast. A layer of straw, then a layer of manure (I prefer cow), then a layer of water with molasses mixed in, then a layer of green stuff, then repeat that again and again until your pile is about 1 m high and 1 metre wide in both directions. Turn the pile every few days for the first week, then once a week after that. When the pile does not heat up significantly after a turn, it's ready - this should be a few weeks, depending on your climate. It will be cool and will look and smell like rich, dark soil.
Easy, quick and you may well have access to the ingredients for making a pile of 'the good stuff' in your backyard right now!
Compost isn't just about piling up layers of straw and cow manure. Observe and tend your pile. Watch the heat, the smell and the size over time.
If it's not hot enough?
We're aiming for a HOT compost here - stick your bare arm in to the middle and the temperature should be just uncomfortable. If it's not or if the pile is not breaking down as quickly as you would like, add nitrogen and check the water content. If it's too dry, add some water the next time you turn it.
Too hot?
If it's steaming and smelly and reducing greatly in size, there's too much nitrogen so add carbon.
Wet and heavy?
If your pile is leaching (water running out of the base) and soggy and heavy to turn, add some dry material on the next turn and consider the size of your materials. If your grass clippings are too fine and matting together, mix in some chunkier materials on the next turn as well.
Consider where you build your hot compost as well - build it on a new planting site, build it higher than your fruit trees or veggie beds so the nutrient that is leached (you won't keep it all in the pile!) is taken up by plants that can use it and/or use the heat generated to preheat your hot water, like Nic and Brad