The LA County Department of Public Works, Environmental Programs Division, hosted one of their scheduled Countywide Smart Gardening Program workshop, on Saturday, July 12.
Over 40 composting neophytes and veterans gathered at the Cynthia Hull Outdoor Classroom amphitheater at Eaton Canyon to find out how to save $700 a year on fertilizers and keep home and garden scraps out of landfills.
The Beginner’s class covered the basics of backyard composting and vermiculture, or worm bin composting, taught by David Carp.
Carp explained the compost method of choice for most residential settings. Warm compost is made in piles, holes, homemade wooden stacking bins or the black plastic bins that were available for sale on site for $40. Warm, as opposed to hot compost, is ready in three to six months for the vigilant composter who turns the scrap heap every seven to 10 days.
The four main ingredients for compost are carbon (“brown” items), nitrogen (“green” items), oxygen and water. The carbon to nitrogen ratio, read as C:N, must be about 30:1 for the three-to-six month decomposition process.
Carbon imbalance is likely since most “green” additions, such as grass clippings and garden trimmings, quickly lose their nitrogen and switch to the carbon team. Adding coffee grounds, tea bags and egg shells to the compost pile increases nitrogen, allowing for continued decomposition.
Suggestions for a healthy compost pile include monitoring ingredients. Don’t add materials exposed to pesticides, avoid aggressive weed and seed additions, avoid grease, meat, dairy products and glossy materials, like paper coated in plastics.
If your pile won’t get hot enough, add nitrogen. Human urine works as a nitrogen additive. What if your bin won’t get hot enough? This isn’t a common problem, but add more green and brown, sprinkle with a hose and stir. Use a thermometer with an 18” or 24” probe to read the interior temperature of the compost pile.
Worm composting requires many of the same materials, but worm bins must be kept in a shady, cooler location. Worms can take temperatures of 60 to 80 degrees. Shade is the best place for a bin. Worm tea is the conversion of food scraps, newspaper, coffee grounds, egg shells. Worm castings or poo, is the black “soil” product made by red worms. This humus is filled with nematodes and protozoa that continue to eat plant and insect material found on the forest floor. As an ingredient for worm tea, this humus is a rich fertilizer when sprayed on plant leaves and roots. Soak the worm castings in aerated water for 24 to 72 hours, then apply directly to plants and soil. Applied every two weeks, worm tea will kill aphids and whitefly and inoculate plants against further invasions.
Future beginning and advanced workshops on various aspects of resource management gardening are available for preview at www.smartgardening.com or at (888)CLEAN LA.