N E X T .

Soil Trust: Belonging-to-the-Field (回歸田嘢)

2021-ongoing Exploring agri-innovation with households of vegetable co-purchasing platform.

  • Soil commons ‧ collectivised nutrients cycling ‧ native bokashi fermentation ‧ food-enabling Hong Kong.

Supported by Hong Miu Organic Farm (康苗有機農場), TinYeah vegetable co-purchasing platform (田嘢), Design Trust (信言設計大使), PolyU Research Institute for Future Food (香港理大未來食品研究院) and PolyU School of Design. Collaborators are Ho-ying Mak, Nicole Lam, Shing Wai Ng, Joshua Wolper, Sheren Ho Yiu Ngan, Kam-fai Chan, Hai-rong Yan, farmer Cheong Gor, Ka-hing Wong, Kevin Kwok, and Wai-ying Pang.

Soil Trust Belonging-to-the-Field
Nutrients cycling revolving around the principle of fermentation: the culturing of both microbial and social life.

Responding to the absence of household-level organic waste recovery in Hong Kong, Soil Trust (泥玩 :集「棄」還田) is building a soil commons — a community of flourishing — around recovering food scraps that brings food consumers and producers together for mutually invigorating local soils. Particular attention is paid to the processes involved to make grassroots nutrient cycling desirable for urban households without land access. The aim of Soil Trust is to (1) make foodscrap cycling an integral part in Community-Supported Agriculture (CSA) for strengthening producer-consumer relations, (2) stimulate eco-farm practice innovation towards probiotic soil regeneration, and (3) demonstrate the importance of a vibrant, localised First Sector in Hong Kong for resource recovery as well as climate change mitigation. Mindful of storage limitations, cultural acceptance issues, and the subtropical conditions of Hong Kong, Soil Trust applies bokashi fermentation to ensure cleanliness and soil regeneration. In bokashi fermentation, layers of kitchen scraps are pressed with alternate layers of inoculated rice bran into an air-tight bucket for maturation. What effectively is an anaerobic, pH-lowering pickling process locks up nutrients over time, and therefore: (a) prevents methane and malodors; (b) proliferates valuable fungi and microbes essential to soil life; (c) functions independently from any electricity and chemicals; (d) integrates flexibly as compost input, soil conditioner, or animal/insect feed; and (e) affords direct community engagement since bokashi production is an enjoyable, social outdoor experience (even more so in pandemic times).

For exploring bokashi fermentation as metabolic link between urban households and local production farms, Soil Trust established since autumn 2021 a field trial inside the Hong Miu Organic Farm (康苗有機農場) with 17 member households of the community-supported agriculture (CSA) platform TinYeah (回歸). At the bi-weekly Farm Care Mornings, the families are invited to produce their bokashi bedding, tend to compost, mulch the soil, and raise the vegetables grown out of it. At their homes, families source-separate, collect, and bokashi-ferment their kitchen scraps, as well as self-document their experience. Families unable to attend Farm Care Mornings send their bokashi-filled bins and receive empty bins as well as bedding supply through the CSA’s weekly vegetable delivery system. The Soil Trust team with the support from the Research Institute for Future Food (香港理大未來食品研究院) provides the necessary know-how transfer, scientific validation, social arena, and material supplies for orchestrating this native bokashi collective. 'Native bokashi' means to upcycle waste with waste whereby all inputs and tools are sourced from locally recovered materials, including: rice bran (bedding), citrus peels (enzyme starter), sawdust (composting), cardboard (mulching), and recycled plastic containers (fermentation).

In fall 2021 member households planted potatoes in the bokashi pilot field fertilised with their fermented foodscraps.
Workshop in source-separating foodscraps and eco-enzyming with participants at TinYeah (田嘢) headquarters in fall 2021.
Producing bokashi bedding self-sufficiently with home-made eco-enzyme and rice bran recovered from the rice mill.
Selective foodscraps are layered with innoculated rice bran bedding and pressed into airtight containers for ‘pickling’.
Participating families adapted the bokashi practice at home and at work conducive to their space, time and close others.
Participants self-document their bokashi journey at home and share it in the group (and towards future exhibition).
Team co-leader Shing Wai Ng experiments with eco-farm praxis innovation via soil-enlivening bokashi and eco-enzyme application.
In bi-weekly Farm Care Mornings, participants help out with maintenance tasks like bokashi processing, bin washing, and mulching.
On Boxing Day 2021, participants inter-planted potato with cabbage and celery seedlings in the bokashi trial field.
To evaluate human-soil relationships, citizen science methods explore nutrients density in crops and bacterial life in soils.
An ongoing bio-chemical trial evaluates soil revitalisation, plant germination and smell acceptance of Soil Trust’s native bokashi.
Biopedagogic Mobilisation
Foodscaps cycling operation piggybacking on TinYeah (田嘢) co-purchasing platform’s existing distribution network.
Climate farming
Farm management innovation guided by Climate Farming principles for buffering weather extremes and sequestering carbon.

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We want our customers to buy local veggies to support local farmers and in partnership with Soil Trust we want our customers to help restore our land resources.

— Director of TinYeah (田嘢) community-supported agriculture purchasing platform —

The Soil Trust program is very fulfilling because we can see and taste first-hand the productive outcome of our waste upcycling. We certainly want to continue this self-made bokashi practice.

— Belonging-to-the-Field participant family and housing estate residents —

It is very meaningful to mobilise citizens in collecting food waste at home that sustains the productive community garden.

— Tertiary educator and organiser of Hong Kong Urban Edible Spaces Forum 2022 —

In a city increasingly focused on turning organic wastes into biogas for energy production, it is important to explore alternatives that revitalise our soils and reconnect people directly with their biophysical foundation.

— Director, organic resource-recovering social enterprise —

Under the current waste policy, all food waste in Hong Kong goes to centralised waste treatment facilities or the landfill. The carbon footprint of these treatments is very big, and the level of resilience is very low. Thus we need to explore how backyards, rooftops and vacant farmlands can be used for composting kitchen waste on community level.

— Program director of Buddhist community and eco-living foundation —

Fixated on the perfect zero-waste solution, only few will ever accomplish it. Soil Trust is exploring a model that may be imperfect but viable for most of us.

— Locavore restaurant entrepreneur —

Soil Trust manifests a fantastic detailed process design in all spheres and across scales. Fascinating possibilities for architecture.

— Urbanist thinker —