1 03/09/2012 1Composting Bill DeKramer

2 03/09/ Sustainability What makes something sustainable?

3 03/09/ Sustainability What makes something sustainable? How then do we define unsustainable?

4 03/09/ Sustainability What makes something sustainable? How then do we define unsustainable? What is the importance of sustainability?

5 03/09/ Sustainability Life on this planet is the flow of nutrients through different life forms Nutrients In Nutrients Out

6 03/09/ Sustainability Life on this planet is the flow of nutrients through different life forms Nutrients In Nutrients Out And, for life to thrive, the nutrients need to come in and go out in the proper the proportions.

7 03/09/ Sustainability What does this have to do with Organic Gardening?

8 03/09/ Sustainability What does this have to do with Organic Gardening? How do we manage nutrients in the food we grow?

9 03/09/ Sustainability What does this have to do with Organic Gardening? How do we manage nutrients in the food we grow? “There’s a universe beneath our feet” - The Soil Solution (movie)

10 03/09/ Topics for tonight Compost and soil structure / value Elements of a compost pile What makes compost work Types of composting Building some models

11 03/09/ What is Compost?

12 03/09/ What is Compost? Nature recycles nutrients as organic matter (OM) in place Composting is a man-made system to recycle these nutrients as OM more quickly and efficiently Composting in one form or another has been used in agriculture since ancient times

13 03/09/ Compost and soil structure What are the structural components of soil?

14 03/09/ Compost and soil structure Structural components of soil –Sand –Silt –Clay –OM

15 03/09/ What ratios would you like in your garden?

16 03/09/ What ratios would you like in your garden? Medium Loam: –20% clay –40% sand –40% silt

17 03/09/ What benefits does Compost bring to the soil?

18 03/09/ What benefits does Compost bring to the soil? Organic Matter (OM) Microbes

19 03/09/ What is Organic Matter?

20 03/09/ Organic Matter Food for soil food web microbes Humus (not hummus) –OM that has reached a point of stability, i.e. won ’ t break down any more –Humus is a colloidal substance, and increases the soil's cation exchange capacity, i.e. its ability to store nutrients in the soil that won’t leach out in a rain.

21 03/09/ Organic Matter Herbicides and pesticides from conventional farming kill not only weeds and pests, but also Organic Matter. As soil organisms die off in their natural, sustainable cycle of life, their structures become the Organic Matter that stabilizes the soil and feeds other organisms. By killing the soil organisms, this cycle ends and the OM build up ends as well.

22 What Makes Compost Work?

23 What Makes Compost Work? Microbes

24 What Makes Compost Work? Microbes One system’s waste is another system’s food (This is a key principle of sustainability) Me: Food (O 2 ) Waste (CO 2 ) Plants:Waste (O 2 ) Food (CO 2 ) In nature there is no such thing as waste.

25 03/09/ What Microbes are in Compost?

26 03/09/ What Microbes are in Compost? Bacteria Fungi Amoebas, slime molds, multi-celled algae Nematodes Bugs

27 03/09/ Controlling Nutrients for Compost Carbon Nitrogen Oxygen Water

28 03/09/ Elements to Control in Compost Food stock (Carbon and Nitrogen) Moisture (Water) Air (Oxygen) Temperature Particle Size pH

29 03/09/ Food stock Carbon sources: –Hay and Straw –Leaves –Black and white newspaper –Sawdust and Wood chips –Old Natural Fibre clothing Nitrogen sources –Kitchen scraps –Weeds (without seed heads) –Animal manure (except dog, cat, pig or human)

30 03/09/ What not to add Kitchen scraps like meats, oils, fish, bones and dairy products Weeds that have gone to seed or spread by their roots (quack grass, etc.) Herbicide treated grass clippings or weeds Dog, cat, pig or human faeces

31 Diseased Plants in Compost There are different opinions about whether to add diseased plants to compost or not. In favor of: –By adding diseased plants, the microbes in the compost that feed on the disease multiply and in this way strengthen the soil food web Against: –The disease may not be controlled by the composting process and spread into the soil

32 03/09/ Carbon / Nitrogen ratio Having the right carbon / nitrogen ration makes a difference in how quickly the food stock breaks down. Ideal is 25 : 1 carbon to nitrogen Current discussion at NOSB is that a range of 15 : 1 to 60 : 1 produces good quality compost

33 03/09/ Common Compost Materials Kitchen / Table scraps 15:1 Grass clippings 12:1 Old manure 20:1 Fruit waste 25:1 Corn stalks 60:1 Old leaves and straw 80:1 Paper 170:1 Sawdust and wood chips 500:1

C / N - Rule of Thumb When adding the materials you’ve collected for your compost, the rule of thumb to achieve the 25:1 C / N ratio is 70% brown and 30% green. Roughly 3 parts brown to 1 part green 34

35 03/09/ Prohibited for Organic Production Prohibited –Sewage sludge –Glossy paper and coloured ink –Paraffin from waxed cardboard (not to exceed.75%) Regulated –Slaughterhouse, hatchery, fish-farm waste –Yeast fermentation waste –Whey –Mushroom compost

36 03/09/ Moisture Ideal is about 50% Rule of thumb: like a wrung out sponge The amount of moisture determines if the pile is aerobic or anaerobic

37 03/09/ Air There are 2 types of compost piles –Aerobic –Anaerobic (Bokashi is fermentation) If an aerobic bin gets too wet, it can become anaerobic and toxic to the other microbes, slowing the decomposition and quality of the compost produced.

38 ･ Performed by aerobes or facultative aerobes under high oxygen conditions. Metabolic breakdown relies on oxygen ･ Organic molecules are completely broken down, i.e. oxydized (burned) ･ Metabolic porducts are carbon dioxide and water ･ Performed by facultative anaerobes under low oxygen conditions. Metabolic breakdown relies on enzymes ･ Carbohydrates and glucose molecules are partially broken down ･ Metabolic products are lactic and other organic acids, alcohols, antioxidants, carbon dioxide, and other other simple organic compounds that can be absorbed by plants and other organisms ･ Performed by anaerobes under no oxygen conditions. Metabolic breakdown relies on enzymes ･ Proteins, polysaccharides, lipids and nucleic acids are partially broken down. ･ Metabolic products are trace elements and smaller organic molecules, gases such as ammonia and hydrogen sulfide, and volatile amines such a putrescine and cadaverine, that can be highly toxic to plants and other organisms. AEROBICANAEROBIC Oxidation FermentationPutrefaction

39 03/09/ Temperature Hot Compost Cool Compost

40 03/09/ Hot Compost (50º-75º C) Relies more on aerobic bacteria Makes compost quickly Can kill pathogens and weed seeds Requires frequent turning Requires attention to brown/green ratio Very fertile, but not as fertile as cool compost To certify as Organic, NOP requires that all feedstock reach 55º C for 3 days

41 03/09/ Hot Compost - Sweden

42 03/09/ Hot Compost - Sweden

43 03/09/ Hot Compost - Sweden

44 03/09/ Cool Compost (25º-50º C) Low maintenance Can be built (layered) over time Takes longer to finish than hot compost Doesn ’ t kill all pathogens or weed seeds

45 03/09/ Particle Size The smaller the particle, the quicker it decomposes For example, grated apples break down faster than whole apples

46 03/09/ pH Ideal pH is around 7 (neutral) Usually don ’ t need to worry about pH if including a wide variety of food stocks, but some things like an excess of coffee grounds can make the pile acidic.

47 03/09/ Types of Composting Layered Worm (vermiculture) Bokashi Sheet composting (permaculture technique)

48 03/09/ A Compost pile is not a garbage pile

49 03/09/ Layered Compost This is the most common form of composting Layered composting is an evolution of the Indore method that focused on the carbon/nitrogen ratios and moisture. Layers of brown and green material are alternated Batch method is when the layers of the whole pile are built in one go. This is usually for the hot method Continuous method is when layers of the pile are built periodically as the materials come available. This is usually for the cool method.

50 03/09/ Building a layer When starting a new pile, lay some coarser material in the bottom to help keep air in Alternate layers of brown and green Sprinkle a handful or shovel full of soil or compost in with each layer as an inoculant Finish with a layer of brown material that acts like a “ scab ” –Up to half the carbon and nitrogen can be lost to the atmosphere if exposed to the sun and air. When starting the next layer, pull the scab back to allow the materials to be in contact

51 03/09/ Demonstration pile

52 03/09/ Composting in Winter

53 03/09/

54 03/09/ Screens for Finished Compost

55 03/09/ Worm Composting (vermiculture) Composts food waste rapidly Bin needs to stay between 12º - 25º C Needs a moist environment (worms breathe through their skin) Worms need oxygen and produce CO 2 pH around 7 but can tolerate Bedding can be cardboard, shredded paper, decaying leaves or peat moss

56 03/09/ Worm Castings Worm castings are very rich –Produce plant-available nutrients –Wide variety of microbes inoculating the rest of the compost pile Worms can produce their weight in castings every 24 hours

57 03/09/ Storing the Worm Bin

58 03/09/ The Worms

59 03/09/ Feeding the Worms

60 03/09/ Demonstration Building a Worm Bin

61 03/09/ Bokashi Bokashi is a Japanese term meaning 'fermented organic matter' Bokashi is anaerobic composting utilizing a starter to inoculate the pile with specific organisms (facultative anaerobes) Quick way to compost food scraps Carbon / Nitrogen ratio is much less important Microbes that grow in bokashi are very different from aerobic compost so it provides differemt nutrients and adds diversity to the soil food web Food stock can include meat and dairy

62 03/09/ Facultative Anaerobes Facultative anaerobes are organisms that can be simultaneously aerobic and anaerobic They adapt to the oxygen level of their environment When low oxygen they switch to their fermenting metabolism, which utilizes enzymes to break down food. Fermentation only partially breaks down the food so it needs to be finished by other microbes

Colette’s Potatoes (2012) Colette added Bokashi bran straight to the soil of one potato plant. 63

Colette’s Potatoes (2012) The plant on the right got the Bokashi bran. It did grow larger, but she mentioned it did not have a greater amount of potatoes growing under the plant. 64

65 03/09/ Sheet Composting Sheet composting is a method of building a garden bed by creating a compost “ pile ” as the bed itself Sheet composting is designed to mimic the natural processes that occur in forests. You build it right on top of grass or weeds so all the natural organic matter that's already there and the microbial populations don't get hauled away with stripping off the sod or weeds.

66 03/09/ Layers in a Sheet Compost Cover the area with cardboard or newspaper and water it in well To accelerate the decomposition of the grass and cardboard, you can put a thin layer of manure down under the cardboard Cover the cardboard or newspaper with organic matter like compost, peat moss, straw, or leaves and water this well so it's like a damp sponge. Plant it. Wherever you want to put a plant, push the straw and leaves away a bit, add a little soil and compost and put the plant in it. This is covered more in Building a Garden Bed

67 03/09/ Quiz

68 03/09/ Summary What are the most important points about composting? Why would you want to compost? How will you apply this information?

69 03/09/ nd Summary Composting is one of the most effective ways to improve your soil and the soil food web There are many ways to create compost. The most important way is your way, the way that fits your time and lifestyle “ Just do it! ”

70 03/09/ Evaluation Please fill out the evaluation form

Thank You for making this course possible, and enjoy putting this knowledge into practice out in the world! 71