Q&A In the Garden, Compost Happens
Updated: Mar 28, 2021
As a Kitsap County Master Gardener, I get a chance to answer some questions that are right up my alley.I have a passion for composting. I still have tons to learn and continue to experiment with a ariety of ingredients and methods.
Here's a question on Composting:
" When will my ingredients turn to rich soil? : I started a compost bin in the spring. [It’s the end of July,] I included dirt from my garden and then some fish compost. I’ve been turning it approximately every three days. When it looks dry, I add water. The volume seems to have decreased, but it doesn’t appear to be converting into soil. It doesn’t smell putrid or like ammonia, so I don’t know whether to add greens or browns. It doesn’t seem to be getting hot, even with our recent warm weather."
Here's my response:
Let’s get you going with my favorite composting trifold from Metro Vancouver BC Canada. They’ve put it all in a nutshell. Here’s the link: http://www.metrovancouver.org/services/solid-waste/SolidWastePublications/HeresTheDirt.pdf.
Some things to think about regarding composting are Location, Size, Ingredients, Moisture, Temperature, and Soil.
Location. Ensure any runoff goes into your garden not into your storm water as it carries nutrients.
Bin Choice and Size. There are many ways to compost from bins and drums, to trenches and planters I describe getting soil from a two bin system and also from a rotating drum below. The exact method you use may vary with the type of set up you have. Enough volume is helpful because the heat builds up in the center A 4 foot by 4 foot footprint for your compost bin is ideal. The standard rotating drum composting systems are about 55 gallons. Those are mounted on a stand which you can clear with your wheelbarrow.
Ingredients. Browns/Greens these are your Carbons and your Nitrogens. Rules of thumb is 1/3 Nitrogen 2/3 Carbon by volume and nothing bigger than your hand.
· Carbon sources include brown leaves, twigs, shredded paper (no receipts the chemical is problematic), toilet paper rolls, and corrugated cardboard (nothing bigger than your hand). Nitrogen sources include fresh cut grass (before the grass goes to seed), used coffee grounds, fruit, and vegetable waste. If you are using animal manure, do not use pig, cat, or dog manure as they carry pathogens. Know that horse manure introduces weedy seeds). Eggs shells ( a great source of calcium), and Avocado pits (nitrogen) take a while to break down, but they will.
· The larger the surface area the faster things break down. So, nothing bigger than your hand goes in. Decrease the ingredient size for a rotating bin to no bigger than your palm. The smaller each ingredient, the better as the increased surface area promotes quicker degradation.
Moisture. Keep your compost wet as a wring out sponge.
Temperature. The heat source is the internal digestion, the furnace. The outside temperature is not going to be an overwhelming indicator of what is going on inside. Humidity may play a part if your compost is in a windy desert like my friend’s in New Mexico, but here in the Pacific Northwest you’ll find even on the coldest winter night, the compost is warm several inches down. You could turn your compost every 3 days when the internal temperature is likely to start to drop. A rotating bin may be unable to stay warm and the contents may freeze. You can bring the rotating bin into a barn or garage or just wait until the weather warms back up again.
Soil from your compost.
· Understand that it will break down a great deal and there will be much less volume of soil than the original volume of ingredients.
· Layer carbon at the bottom, put in your Nitrogen sources (e.g. kitchen scraps and shredded paper), Then top with some soil. Water to be as wet as a wrung out sponge throughout. You may have heard you need worms and perhaps an additive. Worms and other insects to help break down your compost will at first be in the added layer of soil. If you are using a bin on the ground, worms and other bugs will migrate up to it. The additive is also not necessary, given your other ingredients. Just like a moldy sandwich in the refrigerator, compost happens.
· Fill the bin over as long as it takes. It doesn’t have to be full all at once. Keep adding to it. When the first bin is full or the first side of the rotating bin is half full, switch to the next by starting with Carbons at the bottom, add your fresh Nitrogens, then top with a layer from the older pile. Turning and flipping bring in air. If it’s not already wet, add water so the moisture is sponge like. My buddy Marcia adds more dry carbon and sometimes more wet nitrogen to keep that moisture just right in her rotating bins. Give them a couple of turns every day. Marcia also said she got several drums because she and her husband alone have plenty of banana peels and coffee grounds to creates lots of nitrogen. Remember to check with your household before shredding up the newspaper. Keep pieces no bigger than your palm. Marcia bought several because they don't break down immediately and she adds when they get low.
· When you’ve emptied the first bin contents into the second bin and the second bin is filled start again filling the first bin. The rotating bins work best about half full. As you begin to see soil you can filter it out and use it worms and all.
· Filter your mixed compost through a frame with ½ “ (half inch) openings and you’ll have a very nice soil mix. Throw the rest back into your bin to continue to break down.
Rules of Thumb
· 2/3 Nitrogen
· 1/3 Carbon
· Nothing bigger than your hand
· Turn or mix to aerate
· Wet as a rung out sponge
The Rodale Book of Composting, Newly Revised and Updated by Grace Gershuny and Deborah L. Martin, June 5, 2018
Tilth Alliance http://www.tilthalliance.org/learn/resources-1/compost/compost-troubleshooting
· Check with your local coffeeshop and café for their coffee ground waste. It will often include the coffee filters and be moist as a wring out sponge already. So, there you’re set up with your nitrogen, carbon, and moisture.