Research & reports

José Luis Villalpando, Daniel Francisco Chi-Maas, Itzel López‐Rosas, Víctor Ángel Aquino-Luna, Jesús Arreola-Enríquez, Julia Cristel Alcudia-Pérez, Gilberto Matos-Pech, Roberto Carlos Gómez-García, Jesús Froylán Martínez-Puc, William Cetzal‐Ix · Agriculture · Global

This study evaluated a backyard system using 50cm × 50cm pinewood boxes for maize and peanut over nine months. Approximately 213 kg of organic residues were converted into 300 kg of mature compost, and plant development was compared between compost and control conditions. Correlation analyses of morphological properties showed that nutrient effects were positively associated with crop morphology, with maize yields of 9 kg/m2 in compost conditions and 6.6 kg/m2 in control, and peanut yields of 184 g/m2 in compost and 73 g/m2 in control.

Arini Al Ifah, Ila Purnamasari, Zahwa Ayu Wardani, Puguh Bintang Pamungkas · Agroteknika · Indonesia

The effectiveness of liquid organic fertilizer (POC) made from household vegetable waste on the growth and yield of microgreen spinach (Amaranthus tricolor) was investigated using a completely randomized design with four treatments and three replications. Various POC treatments (derived from spinach, potato, and water spinach) showed no significant difference in the growth and yield of microgreen spinach. The treatment without POC, using well water, showed optimal growth patterns and yields compared to the application of various POCs.

Carine Borchert Rosa, Daniela Mueller de Lara, Erli Schneider Costa · Revista Eletrônica Científica da UERGS · Brazil (Rio Grande do Sul)

This study at Escola Estadual de Educação Básica Santa Rita in Nova Santa Rita, Brazil, applied a research-oriented teaching proposal to students, focusing on inorganic functions through organic fertilizer production using school waste. Students built a garden, collected waste, produced organic fertilizer, and validated results. The study observed mutual aid among students, developed their intervention capacity, and noted a positive change in their approach to discarded waste like potato peels, banana peels, eggshells, and mate.

Mamdouh M. Arafa Arafa, Sabry M. Shaheen, A.M.K Mansour, M. F. A. Ahmed · International journal of Environmental Studies and Researches · Egypt

Over the 2020 and 2021 growing seasons at Sadat City farms (Cairo–Alexandria Desert Road, Menoufia Governorate, Egypt), this study tested the effect of compost application on root-rot disease management and tomato productivity. Rhizoctonia solani and Sclerotium rolfsii were isolated from rotted tomato plants as the main pathogens causing root rot and damping-off, which reduced yield. Adding plant residue, cow manure, or compost (plant residue plus cow manure) to soil before transplanting, at a rate of 1.2 kg/m², significantly reduced disease incidence and raised plant survival compared with untreated controls in both seasons. Compost — a tomato-rich organic fertilizer — applied at 1.2 kg/m² produced the largest reduction in disease incidence and the largest increases in vegetative growth (plant height, branches per plant, leaves per branch), yield parameters, flavonoid content, and total phenol content across both seasons; no clear significant differences were found between the plant-residue and cow-manure treatments in plant growth characteristics.

Concepción Santiago Cubas, Concepción Paredes Gil · Modern Environmental Science and Engineering · Spain

A study on Gran Canaria, Spain co-composted municipal and agricultural plant residues with three manure types — chicken, goat and cow — in an open dynamic windrow system of three trapezoidal piles (1.5 m high, 2.5 m wide, 16 m long), mixed at 37.6% straw, 32.7% manure and 29.7% pruning residue by fresh weight. Temperature, humidity and physico-chemical parameters were tracked through the process. All three piles reached the sanitation threshold required by regulation (≥60°C for at least 7 days) and produced compost suitable for agricultural use.

Nadia Nadia, Agus Juono, Dio Ramadan Nugroho, Mifta Nurjanah, Adine Christiningtyas, Marthinus Masriat, E.Y Gitari, Andy Nugroho, Abdurojak Abdurojak, K.J Dahu, Bayu Suseno · Jompa Abdi Jurnal Pengabdian Masyarakat · Indonesia

This community outreach program in Padukuhan Singosaren I, Indonesia — a country ranked second worldwide for plastic waste entering the ocean — used socialization sessions to address low public awareness and inconsistent waste management, teaching a "stacked bucket" (ember tumpuk) decomposition method that processes organic waste into solid and liquid organic fertilizer usable as growing media for urban farming ("hydroganik"). The outreach concluded that well-managed waste can become useful and that community participants were enthusiastic, and it recommends that Singosaren I households adopt the stacked-bucket method at home so household waste can be converted into fertilizer for hydroganik growing media.

Kyle Richardville, Dan Egel, Andrew Flachs, Amit K. Jaiswal, D.J. Perkins, A. W. Thompson, Lori Hoagland · Urban Agriculture & Regional Food Systems · Global

A two-year field trial tested whether amending degraded urban soils with locally made leaf-mold compost could improve soil chemical and biological properties and support the survival of a plant-growth-promoting, disease-suppressive microbial inoculant (Trichoderma harzianum T-22) in tomato (Solanum lycopersicum) production. Compost-amended plots showed markedly higher active soil organic matter and marketable fruit yield in both years, lower foliar disease severity in year two, and reduced transplant-stress deaths from T-22 inoculation in one cultivar, but the authors caution that all composts must be tested for heavy metals or pathogens and that overapplication can reduce crop health.

Bambang Gunawan, Husin Rayesh Mallaleng, Mahrus Ali, Sri Purwanti, Nurlina Nurlina, Fauziatun Nisak, Yeni Ika Pratiwi, Sri Hidayati · Indonesian Journal of Engagement Community Services Empowerment and Development · Indonesia

This report describes a community activity in RW 02, Kalirungkut Village, Rungkut District, Surabaya City, Indonesia, that implemented mass composting technology for urban organic waste as part of empowering urban agricultural land. It was carried out through two approaches: assistance to build expertise and skills in managing mass composting of urban organic waste, and efforts to mobilize community participation. The results showed increased community awareness and participation in waste management through practicing the 3R approach (reduce, reuse, recycle) -- sorting household waste into organic and inorganic at the source -- with the urban agriculture movement identified as an alternative for maintaining family food security and as a contributor to green open space.

Danielle Purkiss, Ayşe Lisa Allison, Fabiana Lorencatto, Susan Michie, Mark Miodownik · Frontiers in Sustainability · United Kingdom

A citizen-science study invited 9,701 UK residents to test how biodegradable and compostable plastics actually degrade in home composting. Many items, including certified products, failed to fully break down; 60% of TUV OK Compost Home-certified items were still clearly visible afterward. The authors conclude home composting is not an effective or environmentally beneficial disposal method for these materials in the UK.

Shimpo N. · Urban Agriculture & Regional Food Systems (Wiley), 6:e20015 · Japan

A case study of a suburban-Tokyo community garden that collects neighborhood kitchen waste and returns it to the soil as compost, forming a local food cycle. It documents how the bottom-up founder sustained the garden, provided work opportunities for people with disabilities and food-education for children, and built links with welfare facilities, kindergartens, and schools.

· Sensors · Global

Optimizes bokashi composting of household organic waste in a smart composting bin, fermenting banana peels with EM-1 brans over 14 days while sensors log temperature, humidity and moisture.

Dsouza A., Price G., Dixon M., Graham T. · Sustainability · Canada

Presents a conceptual framework for incorporating composting into closed-loop urban controlled environment agriculture to recycle nutrients from organic waste streams.

Anjali Mistry, Manfred Spocter · · South Africa (Cape Town)

A study in a middle-class suburb of Cape Town, South Africa, investigated edible cultivation and garden waste management in domestic gardens. While potential gardening space averaged two-thirds of residential plots, 129 respondents primarily cultivated lawns, not food, with minimal vegetable production. Residents often used private gardening services for waste disposal, and on-site garden waste disposal techniques need promotion.

Miriam C. Dobson, Philip H. Warren, Jill L. Edmondson · Sustainability · United Kingdom

This nationwide citizen science project investigated resource demands of urban horticultural production in the United Kingdom using year-long diaries from 163 allotment gardeners. Findings showed an average allotment required 87 annual visits and 139 km of travel. Each kilogram of food produced used 0.4 hours of labor, 16.9 L of water, 0.2 L of topsoil, 2.2 L of manure, and 1.9 L of compost.

Agus Slamet, Maryam Nurlaila, Farid Nur Achmad · Abdimas Singkerru · Indonesia

A community service program in Lapandewa Village, Buton Selatan Regency, Indonesia, provided education and practical training on utilizing organic kitchen waste to make compost, liquid organic fertilizer (POC), and botanical pesticides. Targeting 20 participants, including housewives, farmers, and entrepreneurs, the activity aimed to support food self-sufficiency through urban farming and improve community welfare. Participants successfully learned to produce these items and sort seeds, fostering awareness of waste utilization and motivating a shift from chemical fertilizers and pesticides to organic alternatives.

Leena Erälinna, Barbara Szymoniuk · Sustainability · Finland

This article presents an experimental project in Turku, Finland, aimed at implementing a circular food system in sustainable urban farming. The project had two objectives: reducing food waste in Turku University Campus restaurants and supporting local nutrient recycling by composting food waste for urban farming. The resulting concept, based on two experimental studies, is globally replicable for managing local circular food systems.

A. Varela, Alexandra Sandoval-Albán, Marcela Muñoz, Alfonso Goméz Gómez, Manuel Bogoya, Germán Combariza · Urban forestry & urban greening · Global

This study evaluated the optimal combination of three different modular extensive green roof structures and two types of local substrates (compost and soil + biochar) for Lactuca sativa L. var. crispa (lettuce) growth under tropical climate conditions, measuring physicochemical and biological properties of substrates and plant growth variables over seven weeks under rainy and dry conditions. A monolithic multilayer structure, high Mg concentrations, elevated amounts of 600 μm aggregates, and lower substrate bulk density were linked with higher L. sativa yield, but the specific substrate used was not associated with this result. Some physicochemical and microbiological properties of substrates changed by the experiment's end, with these changes dependent on climatic conditions.

Jonnell Robinson, Sarah Brown, Rose Tardiff, Dennis Brady, Jen Pauley, Mable Wilson · Journal of Agriculture Food Systems and Community Development · United States (Syracuse)

Syracuse Grows is an all-volunteer nonprofit organization in Syracuse, New York, dedicated to food justice. The organization hosts an annual "Resource Drive" event each April, mobilizing community resources to support over 25 community gardens and 3 urban farms. During this event, compost, mulch, and manure are transported across the city, transforming previously vacant lots into spaces for nourishment and camaraderie.

Mary Njoki Mwaura, Sabina Mukoya-Wangia, Japheth Ododa Origa, O.L.E. Mbatia, Evans Chimoita · Journal of Agricultural Extension · Kenya

A study of 149 respondents in Nairobi County examined urban and peri-urban agricultural practices, finding composting and open field farming popular but not the most profitable. More profitable practices like cattle rearing and mushroom farming were unpopular due to expensive inputs and specialized skills. The study indicates that popular practices are less profitable, highlighting a need for transformation towards controlled environment agriculture with policy support.

Mahmudah Hamawi, Use Etica · Prosiding Sains Nasional dan Teknologi · Indonesia (East Java)

This study aimed to examine the effect of growing media mixtures on celery yield. The research was conducted from May to June 2020 at the UNIDA Gontor Faculty of Science and Technology practice land in Ponorogo, East Java. A completely randomized design with one factor and five replications was used to compare four growing media mixtures (A=control, B=soil+compost+rice husk charcoal, C=soil+compost+wood charcoal, D=soil+compost+kitchen ash). Results showed that the soil and compost mixture produced the largest wet weight of celery leaves, which was not significantly different from the soil+compost+rice husk charcoal mixture, but significantly different from the soil+compost+kitchen ash mixture.

Jemima Japakumar, Rosazlin Abdullah, Noor Sharina Mohd Rosli · AGRIVITA Journal of Agricultural Science · Malaysia (Kuala Lumpur)

A field study in an urban community garden in Kuala Lumpur, Malaysia, investigated the effects of biochar and compost on Amaranthus sp. growth and soil properties. Using a randomized complete block design with five treatments, the combination of biochar and compost significantly increased plant height, leaf count, leaf width, chlorophyll content, fresh and dry weight, soil organic matter, and soil organic carbon content compared to other treatments. This combination showed the best effects in enhancing both soil properties and plant growth.

Corinna Schröder, Franziska Häfner, Oliver Christopher Larsen, Ariane Krause · Agronomy · Global

This pot trial with lettuce plants assessed the fertilizer value of composts derived from urban organic waste. Seven treatments, including food waste vermicompost and thermophilic compost from green waste and human feces, were investigated. Lettuce yield and total uptake of P, K, Ca, and Mg were highest with coir-based vermicompost, while fecal compost resulted in high shoot P and K but lower Ca and Mg uptake. All composts required additional nitrogen for lettuce growth, indicating a need for further research on macronutrient availability and alternative N sources.

Tariro Gwandu, Lynsay I. Blake, Hatirarami Nezomba, Jairos Rurinda, Stephen Chivasa, Florence Mtambanengwe, Karen L. Johnson · Environmental Geochemistry and Health · Sub-Saharan Africa

An eight-week greenhouse experiment in Sub-Saharan Africa evaluated the short-term benefits of applying aluminum-based water treatment residual (Al-WTR) with compost and inorganic phosphorus fertilizer on maize productivity. A co-amendment of 10% Al-WTR and 10% compost significantly increased maize shoot biomass (3.92 ± 0.16 g) compared to the control (1.33 ± 0.17 g). Adding phosphorus fertilizer to this co-amendment further doubled the yield and increased maize uptake of zinc, copper, and manganese.

Samuel Ken‐En Gan, Ser-Xian Phua, Joshua Yi Yeo, Zealyn Shi‐Lin Heng, Zhenxiang Xing · Methods and Protocols · Global

This study investigated using mealworms and superworms to consume polystyrene (PS) and their frass as plant fertilizer. Researchers found that small amounts of sucrose and bran increased PS consumption by the worms. Superworm frass, in particular, supported better growth and rooting of dragon fruit cacti over a fortnight compared to mealworm frass and control media. These findings suggest worms could offer a zero-waste solution for plastic degradation and urban farming.

Solomon Tulu Tadesse, O. Oenema, Christy van Beek, Fikre Lemessa Ocho · Frontiers of Agricultural Science and Engineering · Ethiopia

This study in Jimma, Ethiopia, from 2015-2050, used an N mass flow model and field experiments to explore manure recycling from urban livestock farms under four scenarios. It found that livestock manures are the main organic wastes in urban areas, and manure production in urban and peri-urban agriculture (UPA) is projected to increase 3 to 10 times. Critically, only 13% to 38% of manure nitrogen will be recycled in croplands, and intensification of urban livestock production greatly increased nitrogen surpluses, indicating a significant environmental tradeoff.