Research & reports

Jennifer Jevons · · New Zealand (Wellington)

The work of Kaicycle, an urban farming initiative located on Wellington City Council land in New Zealand, was spotlighted. This initiative aims to help the community by improving awareness of soil health, advocating for food waste minimization, growing produce, and practicing regenerative composting. Kaicycle recycles food scraps from the community, composts using anaerobic microbes, and produces vegetable boxes for sale.

Chammi P. Attanayake, Ganga M. Hettiarachchi, Mónica Palomo, Gary M. Pierzynski, Blanca Calderón · ACS Agricultural Science & Technology · United States

The effect of limestone and composted manure on lead (Pb) in vegetables and Pb bioaccessibility was assessed in a contaminated urban garden (total Pb ~200 mg kg⁻¹). Amendments did not affect Pb in vegetables or Pb bioaccessibility. Peeling reduced Pb concentration in radish by half, and removing surface dust reduced Pb in leafy vegetables by 40-50%. Daily Pb intake from consuming lettuce and carrot/beetroot from this garden was approximately 1.5 times higher than the interim reference level proposed by the U.S. Food and Drug Administration.

Ana Karen Ricaño Ochoa, María de los Ángeles Chamorro Zárate Achamorro · South Florida Journal of Development · Mexico (Xalapa)

An environmental education and communication strategy for integrated organic waste management was applied in the Zipor neighborhood of Xalapa, Veracruz, Mexico. This project aimed to raise awareness and provide training for residents, promote citizen participation in organic waste classification and biological treatment, and install community urban gardens for compost utilization. A total of 30 residents, divided into three groups (representing 5% of the neighborhood's inhabitants), participated in three stages: waste separation workshops, compost module construction, and urban garden installation.

Rafael Carvalho Machado, Sieglinde Kindl Da Cunha · Waste Management & Research The Journal for a Sustainable Circular Economy · Brazil (Curitiba)

This study investigated Curitiba, Brazil's Urban Agriculture Program (UAP) and its decentralized composting strategy, which aimed to close the agricultural loop within city bounds. Despite training 24 urban farmer communities in composting techniques, the program was unable to achieve this goal. The research, based on secondary data review, interviews, and participatory observation, identified cultural barriers and conflicts among actor roles within the UAP that hindered the adoption of composting practices.

Felipe Parada, Mireia Ercilla‐Montserrat, Verónica Arcas‐Pilz, Elisa López‐Capél, N. Carazo, J.I. Montero, Xavier Gabarrell, Gara Villalba, Joan Rieradevall, Pere Muñoz · Journal of the Science of Food and Agriculture · Spain (Barcelona)

In spring and summer 2018, in a rooftop greenhouse near Barcelona, coir, vegetable compost from urban organic waste, perlite, and a mixture of compost and perlite substrates were evaluated over three consecutive crop cycles of lettuce. This study aimed to assess the use of substrates made from local materials as an alternative for urban agriculture during periods of water supply cuts. Results showed that compost and the mixture yielded similarly to perlite, and organic substrates increased crop resilience to water restriction.

Dion Notario, Ferdian Suprata, Meda Canti, Listya Utami Karmawan · MITRA Jurnal Pemberdayaan Masyarakat · Indonesia (Jakarta)

A community empowerment program focusing on clean water management, compost making, and urban farming was implemented in Muara Baru flats, Jakarta. A majority of residents responded positively to the program and expressed willingness to actively participate. However, several obstacles hindering the program's success were identified, including a lack of commitment from the local community, climate change, water availability, and arable land availability.

Charles Karani, Eric Obedy Gido, Hillary K. Bett · DOAJ (DOAJ: Directory of Open Access Journals) · Global

This study surveyed 456 urban agro-producer households using an electronically-structured questionnaire to explore informal agro-food waste management and safety measures in low- and lower middle-income countries. Findings showed significant disparities in management and safety practices between participating and non-participating livestock and mixed producers. Waste reduction (86%), utilization (86%), segregation (63%), and composting (58%) were preferred, while disposal (18%) and mixing with salt/dry feeds (24%) were less preferred. Knowledge variables, such as waste sorting and urban agriculture knowledge, had a greater influence on these practices.

Dhian Rosalina, Yenni Marnita, Nasrul Kahfi Lubis, Fiddini Alham · SELAPARANG Jurnal Pengabdian Masyarakat Berkemajuan · Indonesia (Langsa)

This community service activity provided training in Gampong Baroh Langsa Lama, Langsa Aceh city, to 30 day laborers on utilizing household organic waste to create compost blocks for planting media. The training involved socialization, practice, and evaluation, aiming to transform waste into useful products for urban farming. As a result, 50 percent of partners expressed willingness to practice making compost blocks and be periodically evaluated.

Agnieszka Zawadzińska, Piotr Salachna, J. Nowak, Waldemar Kowalczyk, Rafał Piechocki, Łukasz Łopusiewicz, Anna Pietrak · Agronomy · Global

This study investigated the use of compost made from pulp and paper mill sludge, fruit-vegetable waste, mushroom spent substrate, and rye straw as a growing medium for container-cultivated tomatoes. Tomato plants grown in compost-enriched media showed higher leaf greening, more ripe fruit, and increased levels of polyphenols, flavonoids, potassium, calcium, magnesium, and copper compared to controls. Specifically, a medium with 25% compost, 30% high peat, 15% low peat, 20% pine bark, and 10% wood fiber yielded the highest fresh fruit weight, total polyphenol content, and L-ascorbic acid levels.

T. E. Freeman, Tiare Saracino, Lynn Barber, Tom Wichman, Esen Momol, Kristina McIntyre, Jacqlyn Rivas, Jennifer Marvin · EDIS · United States (California)

This is a homeowner-facing extension publication from Florida on environmentally friendly ways to enhance soil fertility for vegetables, herbs, and fruit in home landscapes. It describes recycling nutrients on-site or via composting to build productive edible landscapes with less waste, stating that adopting these methods into landscape maintenance builds organic matter and adds nutrients to soil naturally.

M. Ichwan, Ameilia Zuliyanti Siregar, E Yusni, Tulus Ikhsan Nasution · ABDIMAS UNWAHAS · Indonesia

As a community-service program run from August to December 2020 at Universitas Sumatera Utara (USU), Indonesia, this project set up a waste management unit called SIMALIM, combining smart urban farming methods, at USU's waste disposal site and the rooftop garden of its integrated laboratory, to handle organic waste from campus canteens and nearby residents. It combined black soldier fly (BSF) larvae rearing, eco-enzyme production, and aquaponics (catfish/gabus, tilapia/nila and lele species alongside organic vegetables), training students to participate as eco-campus ambassadors and members of USU's UI GreenMetric team. The project is framed as a model for generating income-producing products from proper organic waste management and improving USU's UI GreenMetric ranking.

Muhammad Taqiyudin Majid, Nurul Aini · Jurnal Produksi Tanaman · Indonesia

Although white radish (Raphanus sativus L.) can be cultivated throughout Indonesia, it is grown in only a few regions; this study examined expanding cultivation via urban farming by testing the interaction between polybag size and planting media composition on growth and yield. Conducted from March to April 2020 in a greenhouse at the Faculty of Agriculture, Universitas Brawijaya, Malang, the study used a factorial randomized group design with two factors and three replications: polybag size (30×15 cm = U1, 35×17.5 cm = U2, 40×20 cm = U3) and cocopeat:compost:sand ratio (1:1:1 = K1, 1:3:1 = K2, 1:1:3 = K3, 3:1:1 = K4). Results showed the appropriate media composition depended on polybag size: the 30×15 cm and 35×17.5 cm polybags produced the highest fresh weight with a cocopeat:compost:sand ratio of 3:1:1, while the 40×20 cm polybag with a 1:1:1 ratio increased the fresh weight of radish tubers.

CGTN · CGTN (China Global Television Network) · China

Beijing implemented compulsory four-category household waste sorting for 21 million residents starting May 1, 2020. One year in, daily waste collection fell from 27,700 tonnes (2019) to 20,600 tonnes (early 2021), the recycling rate reached 37.5%, and separated food-waste volume rose to nearly 11.6 times the pre-regulation level.

Shrestha P., Small G.E., Kay A. · PLOS ONE, 15(4):e0230996 · United States

A study measuring and quantifying nutrient recovery efficiency and loss from compost application in urban gardens. It shows compost often supplies phosphorus far in excess of crop demand, and surplus P can be lost to waterways. The work argues that closing the food-waste-to-compost loop in urban agriculture must be designed for sustainable nutrient management, not just diversion.

Carmen M. Ugarte, John R. Taylor · Urban Agriculture & Regional Food Systems · United States (Chicago)

This study evaluated chemical and biological soil-health indicators at 21 urban-to-periurban sites in Chicago (home gardens, community gardens, institutional farms, and private urban farms). It measured soil fertility, nematode trophic composition and food-web indices, and concentrations of lead, arsenic, and zinc; nematode communities differed by management scale and were likely influenced by soil organic matter and pH. Lead, arsenic, and zinc were below levels of concern, and soil fertility was significantly increased by management, particularly in community gardens and urban farms.

Bruni C., Akyol Ç., Cipolletta G., Eusebi A.L., Caniani D., Masi S., Colón J., Fatone F. · Sustainability · Italy

Reviews Italian legislation and implemented projects on decentralized community composting, arguing Italy can serve as a model for Mediterranean countries building decentralized composting programs.

Mohan S. V. · Materials Circular Economy · India

A case study treating urban organic waste as a resource in urban biocycles, presenting the keyhole garden as a practical decentralized urban-farming method integrating circular-economy and regenerative principles.

Dora Neina, Sibylle Faust, Rainer Georg Joergensen · Chemical and Biological Technologies in Agriculture · Ghana

A study in Ghana investigated the potential agricultural value of charcoal and firewood ashes by examining differences in their chemical and mineralogical compositions and the suitability of various extractants for plant nutrients. Charcoal ash had higher pH, EC, and CCE than firewood ash, while firewood ash contained higher levels of As, Cu, Mg, and Zn, and more Mg-rich minerals. Both ashes contained trace elements, but their bioavailability and plant uptake after field application may differ and may not necessarily lead to plant uptake.

Sugeng Triyono, Fadli Afrizki Surya Aditama, Elhamida Rezkia, D Dermiyati, Jamalam Lumbanraja · World Journal of Advanced Research and Reviews · Indonesia

This pot experiment in Indonesia investigated the effect of medium size and organic compost dosage on the growth and yield of red lettuce. Red lettuce growth was depressed at 1kg and 3kg medium sizes but grew more freely at 5kg. The study found that the 3kg medium size with 10% compost dose yielded 75.3g per plant, which was considered the most optimum treatment due to using the least medium and compost, despite restricted growth.

Cassia Silva Santos Góes · Revista Integrativa de Inovações Tecnológicas nas Ciências da Saúde · Brazil

This paper documents the presentation of the “School Garden Project in Bahia” at the International Congress on Technological Innovation in Health Sciences, held from November 15 to 18, 2017, at IFBA SAJ. The presentation highlighted the school's experiences with a social community garden, including resistances, advancements, garden care outside school hours, and the teaching of composting and natural fertilizers using organic compounds.

Peileku Yikwa, Luluk Syahr Banu · Jurnal Ilmiah Respati · Indonesia

An experimental study conducted at the Greenhouse of the Faculty of Agriculture, Respati University, Indonesia, from February to August 2019, investigated the response of chili and mustard greens polyculture in polybags to onion peel compost composting time and dose. Using a factorial completely randomized design, onion peel compost doses (0, 100, 150, 200 gr/polybag) and composting times (24, 36 hours) were examined. The results showed that applying 100 grams/polybag of 36-hour compost yielded the highest plant weight (211.25 grams) and chili fruit weight (73.25 grams) for polycultured chili and mustard greens.

A. V. Silva, Jamerson Fábio Silva Filho, Dalcimar Regina Batista Wangen, M. L. C. Souza, E. L. Silva · Scientific Electronic Archives · Brazil (Urutaí)

This project at Maria Cândida de Jesus Municipal School in Urutaí, Brazil, engaged elementary students and staff in composting and school gardening to raise awareness about waste reduction, reuse, and recycling. Participants learned about environmental issues, practiced composting with Californian worms, and used the resulting compost to fertilize vegetables in a newly built school garden. The initiative successfully demonstrated student enthusiasm for selective waste collection, composting monitoring, and garden implementation.

Ahmad Shabir Hozad · Environmental Research and Technology · Thailand

This study investigated the effects of human urine as fertilizer on butterfly pea (Clitoria ternatea) plants in a green wall system on the AIT campus. Applied at a nitrogen loading rate of up to 0.73 g N m-2 week-1 (104.28 mL urine m-2 week-1) for 16 weeks, urine fertilizer positively affected the food production, inflorescences, and health of butterfly pea plants, indicating it is suitable for green walls. This method could reduce campus wastewater load and save on expensive wastewater treatment.

Kofi Atiah, Edward Yeboah, Eric Nartey, D.Y.I. Lawson, Volker Häring, Andreas Buerkert, Bernd Marschner · West African Journal of Applied Ecology · West Africa

This study investigated the changes in properties of rice husk and corn cob biochars applied in urban agricultural field soils in Tamale, Ghana, and Ouagadougou, Burkina Faso, over 12 months. Biochars were buried at 20 cm depth, and evaluated based on soil management practices and time. No significant interaction effect was found between soil management practices and time, but time significantly affected most biochar ageing properties. In both biochars, ash content, fixed carbon, cDOC, hDOC, cSUVA, and hSUVA increased, while pH and volatile matter contents significantly decreased.

Ni Made Sudri, Iyus Hendrawan, Mohamad Hardiyanto · Empowerment in the Community · Indonesia (South Tangerang City)

The Indonesian Institute of Technology (BLK) provided integrated waste processing assistance at TPST-3R Batan Indah to support the South Tangerang City Government's waste management program. The challenge was 2000 kg of waste generated daily from 1114 households, with 70% (1.4 tons) going to the Cipeucang landfill. This assistance aims to produce energy and compost, leading to zero waste and supporting urban farming.