Vermiculture CFSA Conference 2016 Rhonda Sherman Horticultural Science Department Vermiculture • Raising earthworms for resale • Focus: ideal conditions for worm growth, reproduction, and health • Usually purchase and haul feedstock or pay for feedstock to be delivered • Make money from sales of earthworms • Sometimes sell vermicompost • Some sell related products: shipping boxes, worm bins, harvesters, soil mixes, books, videos Vermicomposting • Earthworms and microorganisms convert organic debris into vermicompost • Focus: processing waste (not increasing reproduction) • Earthworm size and reproductive rates often lower than in vermiculture systems • Large vermicomposting facility income – tipping fees for waste materials – vermicompost sales – sales of earthworms Vermicomposting Definition Vermicomposting is a process that relies on earthworms and microorganisms to help stabilize active organic materials and convert them to a valuable soil amendment and source of plant nutrients. Not! Vermicomposting is Not Composting Vermicompost is Not Compost Vermicompost Tea is Not liquid from worm bin Vermicomposting is Not Composting • 30 days • 6 – 9 months • Ambient temperature • Pile must heat up • Passive aeration • Must aerate or turn pile – No turning! Vermicompost is Not Compost • Has passed through worms • Microbes broke it down • Contains multitude of microbes • Microbe species and due to stable ambient temp. quantities changed by heat • Sells for $400-$1800 cubic yard • Sells for $0-$35 cubic yard Vermicompost Tea…NOT! • LEACHATE: dark liquid that leaks out of bin • Passed through undigested, anaerobic areas of worm bin • May contain pathogens & anaerobic microbes harmful to people, animals, or plants • Could have sulfides, acids, or high salts • Not recommended for indoor or sensitive plants • Do not use on food crops More “Nots” • “I use red worms not earthworms.” • “We sell 100% pure castings.” • “Some landfill diversion sites are using thousands of pounds of worms to convert tons of waste into vermicompost.” Earthworm Basics • Cold-blooded animal • Hermaphroditic • No lungs: breathes through skin • Dies if skin dries out • Light causes paralysis in ~1 hour Aren’t All Earthworms Alike? • ~9,000 species of earthworms • Half-inch to 22 feet long Three Earthworm Ecological Groups Anecic Live in soil (vertical burrows) Eat soil & litter Endogeic Live in soil (horizontal burrows) Eat soil Epigeic Live in litter (no burrows) Eat litter Use Eisenia fetida for Vermicomposting • Adapts well to living in a bin • Tolerates wide range of environmental conditions • Won’t invade the natural environment They Make More Worms • Cocoon laid 2 days after copulation • Incubation period 18 – 26 days • ~3 hatchlings • Sexually mature in 21 – 30 days • Life expectancy 4.5 – 5 years Conditions for Vermicomposting • Temperature: 59 - 77F (limits 32 – 95F) • Moisture: 80% (limits 60 - 90%) • Oxygen requirement: Aerobic • pH: 7 (limits >5 and <9) • Ammonia and Salt: Low What Will Your Worms Eat? – Kitchen scraps, plate scrapings – Coffee grounds – Livestock manure – Agricultural crop residues – Leaves – Paper, cardboard – Organic byproducts from industries Actually, They Eat… …microorganisms and tiny organic particles Vermicomposting Process • Earthworms ingest microbes • Some are digested, others pass through gut unharmed • E. fetida has indigenous microflora in gut that contributes to microbial community in castings • Grinding action of gizzard promotes microbial activity in wastes as pass through gut • Mucus from intestinal tract covers castings – Provides carbon source for soil microbes – Leads to flush of microbial activity in fresh casts Who is Vermicomposting? • Farms • Households • Prisons • Hospitals • Universities & colleges • Office buildings • Schools & daycare • Military bases • Entrepreneurs • Community gardens Vermicomposting Basics • Start with ~6 inches (15.24cm) bedding • Add composting earthworms • 1-lb (.45 kg) per sq ft (929 sq cm) • Apply 1 inch (2.5 cm) layer of feedstock • Wait until feedstock is eaten before adding more • Cover food scraps with shredded paper, cardboard, cloth, plastic, tarp, etc. How to Vermicompost • Build or buy a bin • Prepare bedding • Add earthworms • Bury food scraps • Harvest and use vermicompost Space Needed • Collect/store feedstock • Worm bins up to 8-ft (2.44-m) wide • Length: depends on your limits • Area to chop/grind food • Place to pre-compost? Utility Needs • Water – Keep worm beds moist (see next) • Electricity – Fans and heating systems – Lights to discourage worms from leaving bins Factors in Choosing Systems • Available on-site area • Quantity of feedstocks • Funding available • Existing buildings • Labor needs & availability • Climate • Predators • State composting regulations • Local zoning and health rules Wooden or Plastic Bin with Lid Bedding for Household Bins • Newspapers • Office paper • Dried leaves • Cardboard • Coir (coconut fiber) • Compost Bedding helps keep bin moist, dark, and discourages fruit flies Pre-Moisten Bedding • Soak 10 minutes in water • Wring out like sponge • Fill bin half way • Add more as it disappears • Spritz with plant mister Bedding for Larger Scale • Stable compost not high in soluble salts • Aged horse manure • Aged leaf mold or shredded brown leaves • Shredded paper, cardboard • Coconut coir Add Eisenia fetida • Start with 1 pound (~1,000) • 1 pound worms to 1 square foot surface of bin • Eat 25-35% of body weight daily • Do not get from yard or bait shop – Would need 33 - 40 bait cups • Buy from a worm grower • Prices vary widely ($22 - $50 lb) Gently Add Worms Add Food Scraps to Small Bin • Use 3-prong garden tool • Pull back bedding • Put in food • Cover w/ bedding • Do not bury food in vermicompost • Wait until food is gone Cover well to prevent before adding more fruit flies and odor Feeding Worms: Larger Scale • Overfeeding is common problem • Add more after last feeding consumed • Nitrogen and mineral content (protein and food value) varies for different feedstocks – Fruit/veggies, manures, grains – VC will differ (effects on plant growth and use rates) • Do not cover top of bed with food; leave room on sides Larger Scale Feedstock Issues • Particle size • Homogeneity • Pathogens • De-worming medicine • Persistent herbicides • Heating up • Pre-composting Pre-Composting • Reduce volume • Destroy pathogens • Kill seeds If gets hot enough! • Reduce heat in feedstock Courtesy: Patrick McNelly Persistent Herbicide Effects on Plants • Stunted growth (main growth tip stops Herbicide Carryover in Hay, Manure, growing and lateral buds begin to grow) Compost, and Grass • Reduced fruit set Clippings: Caution to Hay Producers, • Cupping of leaves Livestock Owners, Farmers and Home • Failure of secondary leaves to grow after Gardeners (Jeanine seed leaves emerge Davis, Katie Jennings) http://content.ces.nc • In legumes, compound leaves stay single su.edu/herbicide- carryover Healthy Worm Bin Traits • Bin smells earthy like forest • Few earthworms are on sides, lid of bin • Bedding is fluffy (has air spaces) • Contents of bin damp not soggy • Earthworms have moist, glistening skin • Small quantities of other critters in bin • Vermicompost accumulating on bottom Be Safe! • Protect yourself and others • Pathogens (e.coli, salmonella, etc.) • Wash hands after handling feedstocks, worms, products • Watch for snakes, things that bite or sting • Mold allergies • Products may contain pathogens, plant diseases, herbicide residues, etc. Harvesting Vermicompost: Small Scale Harvest Vermicompost Method #1: Light Separation Harvesting Vermicompost Method #2: Sideways Separation Harvesting Vermicompost Method #3: Vertical Separation Harvesting Vermicompost: Larger Scale Harvesting Vermicompost: Larger Scale Method #1 • Remove top 4 inches of worm bed – Use a pitchfork – Most worms will be in this layer • Set on top of new bed • Use shovel to remove VC from bed • Draw remaining worms out of VC by laying screen or mesh cloth on top with food on it Harvesting Vermicompost Method #2: Sideways Separation • Start new bed next to working worm bed • Apply food to entice worms to move to new bed • Only feed new bed • After a few weeks, most of the worms should be in the new bed Harvesting Vermicompost Method #3: Vertical Separation • Set tray on top of working worm bed • Tray has screen on bottom or holes that worms can move through • Only feed top tray, ignore bottom tray • Eventually most worms will move up into new tray Harvesting Vermicompost Method #4: Continuous-flow System Harvesting Vermicompost Method #5: Trommel Screen • Remove top 4-6 inches of worm pile with pitchfork • Pitch into rotary trommel screener • Vermicompost comes out through 1/2-inch or ¼ inch screen, worms come out of end • Use shovel for rest of pile What Vermicompost Does For Soil • Improves soil structure • Increases moisture infiltration • Improves & stabilizes soil pH • Increases moisture-holding capacity Courtesy of Tom Herlihy VC Effects on Plant Growth, Disease & Pest Suppression • Increased rates of germination, growth, flowering and fruiting • Improved root development and stress tolerance • Decreased transplant shock • Increased plant vitality and flavor profile • Decreased attacks by plant pathogens, parasitic nematodes, and insect pests Turnips Grown w/ 0%, 10%, 20% Swine Manure Vermicompost Pythium Suppression 4.0 Control Sterilized VC Unsterilized VC a 3.5 ab b b 3.0 2.5 2.0 c 1.5 c c 1.0 Disease SuppressionDiseaseRating SMM SMM + SMM + SMM + SMM + SMM + SMM + 10% 20% 40% 10% 20%