The practices involved with gardening and urban farming often reinforce the virtue of patience. Homegrown compost—a grower’s black gold—demands time. In addition to time, composting requires the right amount of aeration, a balance of carbon and nitrogen, and exposure to heat.
As a compost newbie, I waited anxiously for my barrel full of yard clippings and vegetable scraps to magically morph into crumbly bits of nutrition for my garden without toiling with the pile. In truth, it took about one year and a bit of hacking with a shovel for my compost to finally mature. That was before I learned the secret.
When you have the right balance of matter and conditions for decomposition, grinding or shredding your compost pile is the most effective way to speed up the process. According to a study from the University of California-Berkley, material will decompose faster when broken up into 1/2-inch to 1 1/2-inch pieces. Woody, hard pieces should be broken up into even smaller bits.
If you have a yard, this can be accomplished at any time by mowing over the contents of your compost bin—but proceed with caution. Any woody pieces or large pieces can fly out of a standard push-mower and ricochet into the air. Before mowing over your pile, look through the material for large, hard pieces, such as sticks or yard waste, early in the decomposition process. Remove anything with the potential to resist grinding in the mower. Give the pile a straight-forward mow-over one time. Then, after turning off the mower, go back through and collect your pieces, returning the ground pieces to the compost bin.
Another trick for grinding up compost can happen in your kitchen. Before emptying your kitchen vessel of table scraps into your outdoor bin, run the content through a food processor or tough blender. Make sure the pieces are 1/2 to 1 inch. This will prevent the watermelon rind that refuses to decompose from stalling your progress to rich, nutritious compost.