Your Trash is My Treasure

According to the United States Environmental Protection Agency, up to 26% of solid waste (about 68 million tons!) dumped into American landfills each year is made up of food scraps and yard trimmings that could otherwise be used towards soil building and improved food production. Lucky for the home gardener on a budget, compost is one of the best and least expensive ways to help your garden thrive during the growing season while also reducing your solid waste contribution to municipal landfills.

Compost is a combination of carbon and nitrogen-rich plant matter that has decomposed into a dark, earthy-smelling, soil-like result known as humus, Latin for "earth" and "ground". Humus provides garden beds with plant-loving nutrients while it also improves soil structure, providing better air-circulation and moisture-retention. Decomposition of plant material into humus relies on elements such as air and water in addition to the work of many tiny creatures like insects, worms, and microorganisms such as bacteria and fungi; as these creatures chow down on our food and yard scraps, they produce the necessary heat and castings that turn our waste into humus. Humans can also help the process by providing the proper environment for pile decomposition, as discussed below. Gardeners can buy a composting bin, build their own using materials such as wood and wire, or simply make a big, free-standing heap! Getting started is as easy as adding the following waste items to your pile:

Carbon or "Brown" Matter:

• Fruit peels and pieces
• Newspaper and cardboard
• Fireplace ashes
• Wood chips and shavings (untreated!)
• Leaves and pine needles
• Twigs and sticks
  
• Straw
• Nut shells and corn stalks
  

Nitrogen or "Green" Matter:

• Vegetable peels and pieces
• Food waste
  
• Grass and hay
• Eggs shells
  
• Coffee grounds and tea bags
  
• Seaweed
• Weeds (decrease risk of spreading weeds by completely drying out all weeds prior to composting and leaving out particularly invasive varieties)
• Leguminous crops (alfalfa, clover)
• Manure
  

Home gardeners should NOT compost the following:

• Meat and dairy foods (get too stinky and attract larger animals)
  
• Coal ashes
• Color-printed paper and cardboard
• Diseased plants
• Invasive weeds
• Pet waste
• Synthetic chemicals
  

The saying goes "compost happens," but for those with less patience and nutrient-depleted soil, it doesn't seem to happen soon enough! However, there are several composting techniques available to gardeners and farmers alike, including:

Cold or slow composting, a maintenance-free way to compost; as simple as adding organic matter to your pile and waiting for nature to run its course,
Hot composting, a more intensive technique relying on a higher pile temperature for quicker decomposition, and
Vermicomposting, a form of composting utilizing the decomposition powers of worms

Looks like too much carbon and too little moisture!
Fall 2010

While it can take several months to a year for adequate decomposition to have taken place, you will be more than happy to see the effect this natural fertilizer has on your harvest once applied to your garden beds. Use the following suggestions to help quicken the decomposition process:

• Cut up matter into smaller pieces that microorganisms can decompose more quickly
• Try to maintain a good carbon:nitrogen balance (the EPA suggests 1 part "brown" matter to 1 part "green" matter, though other sources recommend a larger amount of carbon-rich matter); add extra "green" matter to increase pile heat or extra "brown" matter if the pile starts to stink
  
• Turn (mix) your pile to aerate it
• Try to maintain a good moisture balance; too little water can kill bacteria and stop decomposition while too much water can make a pile slimy and stinky and halt the action of aerobic (requiring oxygen) microorganisms
  
• For faster compost, try to maintain a pile temperature between 120-160 degrees F during warm seasons; positioning your pile in a sunny area and adding matter in large bunches (as opposed to small amounts) helps maintain high temperatures

Composting during the Winter

During our cold and snowy New England winter, most if not all outdoor decomposition comes to a halt unless the pile is kept warm enough for microorganisms to continue their work. Unless you already have a large, established pile or a well-insulated bin, you should start your own compost after winter conditions have passed. However, many local farms and composting facilities are happy and willing to let you dump your compost-approved waste onto their mammoth piles during the winter months. Be sure to first discuss your desire to provide food and yard waste with farm and facility staff PRIOR to dumping anything, as every organization has its own set of rules and stipulations that should be respected!

We will further explore these different forms of composting this spring and summer in the Learning Garden and on our blog, but for now, save your scraps and stay toasty!

Rebekah

Composting suggestions based on data provided by the USDA Natural Resources Conservation Service, the University of Missouri Extension, and the US Environmental Protection Agency.
Images by Rebekah Carter (2011).