Friday, March 30, 2018 | 2 a.m.
Grocery store to fridge or farm to fork—however you source your meals, it’s likely food waste piles up along the way. Composting is a great solution for these scraps and spoils, and for home gardeners, the process creates a rich fertilizer that can help improve soil water capacity, nutrient levels and malleability when mixed into your garden.
Composting is also a fantastic way to decrease household waste. According to the United States Environmental Protection Agency, food scraps and yard waste make up almost 20 to 30 percent of what we throw away each year—prime potential compost tossed aside when it could be nourishing plants in your very own yard.
What Is Composting?
Compost is decayed organic matter broken down by microbes into a rich, dark substance that smells like fresh earth. It can be achieved via several methods:
Slow/Cool/Passive Method
Compostable materials placed in a bin or pile, with little to no maintenance. It can take up to a year for microbes to process the materials and yield compost. Great for those who need only occasional compost or who generate little waste.
Hot/Active Method
Compostable materials purposefully layered in a pile, bin or tumbler and consistently mixed to keep a core temp of around 120-160 degrees. Can process within weeks. Great for those who need and create higher volumes of compost.
Vermicomposting
Special type of composting using Eisenia fetida, the red wiggler earthworm, which eats its weight in organic matter every day. Worms are kept in a covered container in a bedding of dirt, shredded newspaper or dried leaves. Compost materials are added for worms to eat and the result is nutrient-rich worm poop called “castings.” This method doesn’t use as much space as a traditional compost heap and is ideal for apartments and urban dwellings. For worms bred especially for the desert climate, visit lasvegasworms.com.
The four basic ingredients you need to start composting
1. Carbon. From brown materials like shredded paper, leaves, straw and other dry yard waste
2. Nitrogen. Green materials like garden trimmings, grass, vegetable and fruit scraps
3. Air. Allows microorganisms to work.
4. Water. To keep things moist and warm.
How to compost
While there are different methods for composting, one of the most popular is the three-bin hot compost method. The University of Nevada Cooperative Extension office recommends the following:
1. Site. Pick a bare-soil site that is level, well drained and close to a water source. Keep it partially shaded to prevent moisture from evaporating.
2. Pile size. The most effective piles or bins measure one cubic yard. Maintain a series of three bins for different stages of decomposition.
3. Ingredients. Maintain a ratio of 1:2 green materials to woody materials. Add a bit of soil or finished compost every 9-12 inches as a starter.
4. Particle size. Aim for particles that range anywhere from a half-inch to 1.5 inches. Anything smaller compacts. Anything larger takes longer to break down. Shred or chop woody plant material.
5. Water. Moisture is hard to maintain in the desert, but too much water is also bad. Compost should be kept damp, like a wet sponge wrung out. Too little water and the compost will take longer to decay. Too much water and nutrients may run out, or unpleasant odors and pathogens may form. Cover piles during heavy rain.
6. Mixing. Turn piles weekly using a pitchfork for aeration. As one pile begins to heat up (temperature naturally increases within the pile as organisms work to break down materials), start a new one. By the time the third bin starts working, the first bin should be usable. Test the temperature using a thermometer or your hand. Aim for 120-160 degrees, or a temp that is uncomfortably hot to the touch.
7. Curing. A working pile should stay hot for several weeks, then begins to shrink by half. Let it sit for another four to eight weeks to “cure” or cool down to 80-110 degrees. Once it cools, it’s ready for use.
Can It Be Done in the Desert?
According to Angela O’Callaghan, social horticulture specialist for the University of Nevada Cooperative Extension, Clark County, there are plenty of common excuses for not composting in a desert climate, but they’re mostly misunderstandings.
Compost misunderstandings vs. compost reality
• Only grass clippings are compost material. Reality: Any plant material can be composted.
• Materials will never break down in this climate. Reality: Breakdown happens no matter what, but moisture helps facilitate it.
• It takes too much time. Reality: Average maintenance only takes 30 minutes a week.
• It takes up too much space. Reality: A three-bin system can require 81 cubic feet, but a single vermicomposting bin may require only two cubic feet.
• It smells foul. Reality: Successful compost smells sweet and woodsy.
What can you compost?
• Lawn waste
• Herbivorous animal manure (cow, goat, chicken, etc.)
• Non-animal kitchen waste (vegetables, fruit, coffee grounds etc.)
• Eggshells
• Nutshells
• Non-diseased garden trimmings
• Newspaper, paper towels, paper (sparingly)
• Untreated woodchips, sawdust
• Fall leaves
• Dry cornstalks
• Hay, straw
• Coffee filters and tea bags if made of natural, uncoated material
• Wood fire ash (sparingly)
What can’t you compost
• Yard or garden waste treated with pesticides
• Omnivore/carnivore manure (dog, cat, swine, etc.)
• Synthetic fertilizer
• Meat or fish bones and scraps
• Dairy products
• Oils, fats, grease
• Diseased plants and trimmings
• Poisonous or toxic plants
• Glossy or coated paper, stickers
• Treated woodchips, sawdust
• Weeds
• Plants with too many tannins or resins (pine, juniper, cottonwood, etc.)
• Charcoal ash (high pH)
Not all organic matter can be composted
It all breaks down, but there are certain materials you don’t want mixed into your soil. Dairy products smell awful when rancid and are known to attract animals. The same holds true with oils, dressings, margarine, grease and other fats. They also form vacuums within the soil, starving helpful bacteria and fungi of oxygen. Avoid diseased plants or flowering weeds. Temperatures inside the compost may reach up to 160 degrees, but that’s not hot enough to kill most diseases and seeds. Likewise, avoid dog and cat feces, as it can contain harmful bacteria and parasites.
Extra tips:
• Don’t disturb already established plants by trying to add compost to their roots. Instead, brew a compost tea for the occasional “green up.” There are several methods for making compost tea, so pick the one right for your set up.
• If you garden, compost! It’s one of the best ways to improve soil health, fertility and workability.
• Avoid citrus peels, onions and garlic if vermicomposting. The high acid content will kill the worms and slow down decomposition.
