The Pittsburgh Urban Gardening Project

The Pittsburgh Urban Gardening Project is a nonprofit organization dedicated to educating people in ways to live healthy, sustainable lives.  We plant, grow and harvest fruits and vegetables around Pittsburgh with the goal of turning city streets into healthy eats.

Composting Basics

As the weather continues to warm and Mother's Day approaches, I decided to build my mother a compost bin and log shelter to help fertilize her garden and put her compostable materials to good use.  I started building today but more importantly, put together a starter guide for her so she knows what to do when it is built.  Here, I share the guide with you so you can all start your own compost as well.

  • Compost should be 3 parts “brown” (dead leaves, dead plants, straw, shredded paper, shredded twigs, pine needles, sawdust from untreated wood) which is high in carbon and 1 part “green” (fresh grass clippings, garden prunings, green weeds, manure, seaweed or pond algae, non-meat, non-dairy kitchen scraps) which is high in nitrogen

  • Do not use house pet feces!!!

  • You should bury all the plant food waste in the center of the pile and cover the top of the pile with a one-inch layer of soil, dry leaves, or finished compost to avoid attracting flies.

  • One way to test if your compost is finished is to seal a small sample in a plastic bag for 24 to 48 hours. If no strong odors are released when you open the bag, the compost is done.

  • Chop or shred large pieces to 12 inches or shorter (thick, woody branches should be chipped, ground up, or left out).

  • One of the most common mistakes in composting is letting the pile get too dry. Your compost pile should be moist as a wrung-out sponge. A moisture content of 40 to 60 percent is preferable. To test for adequate moisture, reach into your compost pile and grab a handful of material and squeeze it; if a few drops of water come out, it's probably got enough moisture, if it doesn't, add water. When you water, it is best to put a hose into the pile so that you aren't just wetting the top. You can also water as you are turning the pile.

  • Not all bugs are bad. In fact, all bugs play a role in nature. Many compost pile organisms eat other organisms and turn them into compost. At least one-third of the volume in a compost pile is made up of the dead, decomposed bodies of soil organisms.  Still, you don't want just any old bugs in your compost pile. So lets learn about what you might find in your compost pile so you'll be able to decide whether there really is a problem or not.  The food web decomposition process is divided into three levels:
  1. Level 1 is made up of herbivores: bacteria, fungi, actinomycetes, nematodes, mites, snails, slugs, earthworms, millipedes, sowbugs and worms. Note that some types of mites are carnivores. 
  2. Level two is comprised of the organisms that eat level one organisms.  It includes both herbivores and carnivores: nematodes, protozoa, rotifers, soil flatworms, springtails, some types of mites, and feather-winged beetles. 
  3. Level three is comprised of the organisms that eat level two organisms.  It includes centipedes, mites, rove beetles, ants, spiders, psuedoscorpions and earwigs