By @medsforheads

Some of us may have seen or even built a compost pile as a way to divert our kitchen scraps and dead houseplants from landfills and return them to the earth as they break down. But did you know compost provides vital support to all kinds of plants including cannabis? Troy Hinke, owner of Living Roots Compost Teas, helps gardeners at the home and commercial level harness the power of decomposition. I met Hinke presenting at NECANN earlier this year and caught up with him recently over the phone.

Working at the Rodale Institute, a 333-acre research center and recognized authority on organic farming, Hinke apprenticed under then-Chief Research Scientist Dr. Elaine Ingham performing soil microscopy and eventually taking part in a study of compost that would support a change in national quality control standards.

Hinke and his colleagues developed a more biology-based paradigm they called “turn according to temperature,” which requires farmers maintain the balance of heat and moisture in their compost attentively. Regular turning ensures the microscopic life that drives the compost pile is well fed and oxygenated.

“To meet organic regulations for windrows or turned compost, you have to be between 131 and 160 degrees for fifteen days and turn five times,” said Hinke. “That’s kind of loosey-goosey because you could go out there on the fifteenth day after having had your compost soaring in temperature, going completely anaerobic, and turn it five times when it’s now full of unwanted microorganisms.”

Why does compost heat up?

Bacteria and fungal spores are ubiquitous in the air and attached to organic matter. As these aerobic microorganisms feed on the carbohydrates that make up plant tissues and reproduce throughout the pile, they release CO2 and energy in the form of heat. Past a certain point, however, as oxygen gets consumed, temperatures can start to climb past 160F, threatening the sustainability of the ecosystem. If the compost becomes anaerobic, or devoid of oxygen, beneficial microbes will die, creating a smelly mass full of toxic alcohols and phenols. To avoid this issue, Hinke recommends implementing forced air or negative air in a perforated pipe system to create an aerated static pile.

Using Compost in the Garden

Plants can receive the benefits of compost as a top dressing, an amendment to soil, or in the form of a liquid extract. The mycorrhizal fungi and bacteria that populate the compost form symbiotic relationships with plant roots, feeding on the sugars they exude. In return, the microbes provide not only nutrients but protection from harmful fungi such as molds, powdery mildew and fusarium by crowding them out and not giving them a chance to spread.

Hinke’s company Living Roots offers compost tea brew kits consisting of fresh compost, a mesh bag, and some additional food for the microbes to allow users to concentrate the active properties of compost for use in sprayer or hydroponic systems. The particles of sediment that permeate the mesh can accumulate in irrigation lines and reservoirs, so it’s especially important in these cases to clean equipment regularly.

Compost tea can be diluted per the user’s needs and applied monthly or biweekly to replenish the living microbiome, though each batch should be used within about 48 hours of brewing. In addition to warding off pathogens that cause plant diseases in cannabis, many growers claim that a “living soil” replete with good organisms contributes to the production of terpenes less commonly achieved with synthetic salt-based nutrients. Compost tea can even be used as a foliar spray to create an impenetrable sheath on the surface of leaves.

Five Essential Composting Tips

1. Construct a Heterogeneous Pile: “You can consider compost fertilizer, in a way, but it’s more accurate to consider it an innoculant,” says Hinke. Adding a diverse array of matter introduces a community of organisms that collaborate to decompose pieces of fruits, vegetables, leaves, woodchips, and any other inputs into an extended-release bank of nutrients. In particular, leaves and native soil in wooded areas are often rich with saprophytic fungi that can accelerate the breakdown of hardier material.

 

2. Be Patient: Compost isn’t made overnight; it takes time for microbes to thoroughly process organic waste. “Depending on management methods, you can get decent compost within 90 to 120 days. Normally, it’s going to take at least six to nine months, sometimes a year. I keep compost for up to two years as the biology continues to change so I can get a robust microbial spectrum.”

 

3. Keep compost moist: Water creates a more hospitable environment for bacteria and fungi, but too much can cut off access to oxygen. “It’s better to let the pile dry out than it is to completely flood it, but once compost dries out, a lot of those microorganisms go dormant, and only some will come back when you wet it again.”

 

4. Turn, turn, turn: It’s crucial to ensure thorough aeration and control the heat of your compost pile by turning it frequently with a shovel or pitchfork at least every few days, depending on the composition. “If you’ve got really high nitrogen, your pile can hit 170 degrees in a matter of hours.”

 

5. Manage space realistically: If you don’t have a yard to set up a sizable compost pile, it may be tempting to use one of many DIY methods detailed online to compost in a tote bin or trash can with holes drilled in the sides. However, growers in this situation may be better off enlisting some help from our limbless wiggling friends. “I’m not a fan of the trashcan method because you’re normally not turning it that much, so even though some air can get to the sides, the center and bottom is going to get packed up and most likely go anaerobic. So, in a smaller space, I would recommend people use worms to do vermicomposting.” Hinke’s other company Urban Worm sells a vermicompost bag with a flow-through feeding system about the size of a dishwasher from which users can collect fresh worm castings.

Check back soon for more Scientific Grow Journal entries. Visit our YouTube page for Scientific Grow Journal videos. Follow all of our Grow Journals here.

For more Illinois cannabis industry news, click here.

To learn about cannabis-friendly events in Illinois, click here.

For Illinois News Joint reviews, click here.