Urban Ecological Agriculture Versus Land Scarcity: A Tale of Two Realities Based on 6 Indonesian Cities

1. Introduction

The need for housing and industrial development in metropolitan cities drives rapid urban land sealing, urban expansion, infrastructure development, and, ultimately, land scarcity. This urbanisation tends to consume arable land and pushes farmers away from the vicinity of cities. It further widens the gap between urban and rural livelihoods, potentially leading to spatial injustices. Urban agriculture (UA) is an emerging critical strategy to address the challenges posed by rapid urbanisation [1,2]. As cities expand, food demand, and hence the need for food production, also increases. This requires alternative solutions (other than food production in the vicinity of the urban areas, or via food collection and distribution centres) to ensure food security [3]. Kurnianto [4] explores the potential of UA to mitigate the effects of urbanisation, including limited land availability, environmental degradation, and food deserts. It examines various urban farming practices, such as rooftop gardens, vertical farms, and community gardens, highlighting their benefits in promoting local food systems and enhancing community resilience. UA initiatives are thus effective in improving food access, reducing carbon footprints, and fostering social cohesion, yet they also face certain constraints and requirements. Supportive policies and community engagement may still be necessary to maximise the potential of UA; it needs to be integrated into urban planning as a whole to provide sustainable solutions.

The Indonesian institutional context for addressing food security and UA is instructive for understanding how and why urban agricultural initiatives may be successful from a food production output perspective [5], yet simultaneously harmful from a land-scarcity perspective [6]. Indonesia’s rapid urban growth not only consumes productive agricultural land but also, at the same time, protects green public spaces and food security through its urban policies. The RTH – Ruang Terbuka Hijau (Green Open Space) policy requires cities to keep at least 30% of their total area zoned for green space. At least 20% of this space should be public (i.e., free for anyone to use), while the remaining 10% may be private. These 30% zones are protected, forbidding the construction of any buildings, offices or stores. Moreover, at the national level, programs such as P2L (Pekarangan Pangan Lestari), originally known as KRPL (Kawasan Rumah Pangan Lestari) and initiated by the Ministry of Agriculture in 2010, provide the institutional frameworks for such policies. The vision of this program was to have every yard of a house in Indonesia filled with food crops. The national program, run by the Food Security Agency, continued until 2019 and, in 2020, became the P2L program, with the aim of expanding the number of beneficiaries and maximising the use of yards for nutritious food crops.

By 2024, the P2L program had reached more than 11,000 farmer groups throughout Indonesia with a budget support of Rp250 billion per year. More than 70 thousand yards are now productive food parks that help meet household food needs. The crop from P2L has helped 1 million families reduce their food spending by up to 20%. Chilli, one of the commodities that is often a concern due to price fluctuations, can now be picked directly from the yard. P2L also has a significant impact on the decline in stunting rates. In East Nusa Tenggara, for example, the availability of fresh food from P2L helped overcome malnutrition. The success of P2L also extends to urban areas such as Jakarta, Surabaya, and Bandung, which have begun to adopt this concept through urban farming. By 2025, the government targets the addition of 15 thousand new farmer groups and the development of the unified P2L model. Besides food crops, the program aims to include small farms for poultry and fish as well, to create a sustainable food system¹.

A key problem in the debate on UA and the advocacy to promote urban food production, which remains insufficiently investigated, is its effects on urban land scarcity, the consumption of productive land, and the need for public urban green space. While the benefits of UA are clear from the perspectives of food security and sustainable transportation and production, urban planning is ultimately a process of finding optimal trade-offs in land allocation amid competing land demands. Although UA may offer a reasonable and sustainable solution, allocating certain urban spaces to it may reduce land availability for other purposes, resulting in an overall increase in land values.

This article, therefore, challenges the benefits of UA from a land-scarcity perspective, as it ultimately contradicts the socio-spatial necessity and value of agricultural land and creates greater agricultural land scarcity than when agricultural land is preserved or restored. The key questions this article poses are therefore:

(1) Which land scarcity types emerge from UA initiatives? This includes investigating the constraints and obstacles from land scarcity and land management perspectives that influence (and possibly determine) the success or failure of UA initiatives.

(2) Which governance structures influence the land constraints and contribute to the success of UA initiatives? This includes investigating the contributing and contextual (policy) factors to the success and failure of UA initiatives.

Addressing these questions starts with a theoretical perspective on UA, land scarcity and the land governance sustainability nexus, which are each important for the understanding of theoretical and practical contradictions and dilemmas and the assessment of their interconnectedness. It then describes the methodology for data collection and analysis, followed by an overview of key findings for each city. These findings form the basis for a discussion section on the effectiveness of programs supporting UA, the implications for the land scarcity spectrum, the governance architecture, and possibilities for sustainability and resilience. The final section concludes by answering the main research questions.

2. Theoretical Perspective

To contextualise the debate over providing space for UA versus the land scarcity it causes, it is necessary first to define UA and distinguish it from related terms and concepts. Secondly, one needs to understand land scarcity as a structural variable. And, thirdly, the outcome of the trade-off of UA and land scarcity needs to be conceptualised as a land governance sustainability nexus.

2.1. Urban Agriculture Versus Urban Farming

Academic literature often uses the terms UA and urban farming (UF) interchangeably. However, if publications make a difference, then UA is usually described as a broader concept, whereas urban farming tends to refer to the specific business of farming. Urban farming encompasses all the ways people grow food and raise animals in or near cities, including community gardens, backyard patches, school projects, and city farms, typically with the aim of providing social and environmental benefits. Side effects are improving social cohesion and neighbourliness in cities, and occasionally cooling the city. Urban farming tends to refer to the business-oriented subset of UA, profit-oriented, output and production-oriented and measured through efficiency indicators. Goals may include supplying food to local markets, restaurants, and community-supported agriculture programs. Conceptually, UA is understood as a macro-level spatial and socio-ecological phenomenon that encompasses all food and non-food activities within city boundaries and/or the peri-urban fringes [7]. FAO defines UA as practices that produce food and other outputs through agricultural production and related processes (transformation, distribution, marketing, recycling, etc.) that take place on land and other spaces within cities and surrounding regions²- Hence, it involves the cultivation of crops and the rearing of animals within cities, integrating local waste management and urban greening infrastructures. UA is segmented into three motivation-driven dimensions: self-supply (subsistence/household), sociocultural (community engagement) and commercial. In contrast, urban farming is more of a market-oriented venture, directly associated with job creation, technological inputs, food security metrics and high-yield financial returns [8].

UF literature focuses, among other topics, on high-tech, climate-controlled, and building-integrated systems, such as hydroponics, aquaponics, and vertical arrays. Typically, urban farming products are short-term crops like leafy greens (e.g., water spinach, spinach, bok choy, lettuce), chilli peppers, fruits (e.g., tomatoes, small melons), and herbs, often grown in vertical gardens. Fish (e.g., catfish) can also be raised – typically in tanks beneath hydroponic plant setups [9,10]. The sustainability claims for UA are framed as delivering social and ecological benefits (e.g. local biodiversity, urban heat island mitigation and community cohesion) [11], whereas UF's claims are primarily about economic benefits (e.g., local employment, water-circularity efficiency, and consistent food yields).

2.2. Land Scarcity as a Structural Variable

There are different types of land scarcity, especially in the global south and especially in areas affected by natural hazards. One can differentiate area-based, value-based, people-based and ecology-based land scarcity. For area-based scarcity, the amount of area (km2) is not sufficient for functional land demands, including housing, agriculture, industry or infrastructure [12,13]. For value-based scarcity, the amount of available land value exceeds available funds to manage or convert the land [14,15]. People-based land scarcity refers to the problem resulting from an amount of population, or the type of households (e.g. single, family), which exceeds a minimum set standard area which a person or household requires [15]. Ecology-based land scarcity refers to a problem of carrying capacity, which is not enough for the demand for ecological (service) functions, such as green, biodiversity, and conservation areas [16]. Especially in South and South-East Asia, all these types of land scarcity increase, not only by fast population growth in the past decades, but also by fast-changing urban livelihoods and socio-economic transitions, which are too fast and too complex for institutional structures and governance frameworks to adapt [15]. The result is a human-land imbalance, speculative inefficiency, price-driven displacement and a transformation of both urban and agricultural landscapes into fragmented built-up clusters [17]. Additionally, it may lead to what is referred to as ‘the paradox of idleness’, homesteads remaining idle, not because of declining or increasing value, but due to institutional rigidity [18]. In short, land scarcity is not a fixed condition, but a product of market dynamics, planning and zoning decisions, and the political economy of land. In connection to UA, land is occupied or converted through private yards, vacant communal plots, public rights-of-way (e.g., alleys), rooftops or riverbanks. These choices may be both voluntary (through formal decisions or informal occupation) and involuntary (e.g., through eviction or resettlement).

2.3. Land Governance Sustainability Nexus

Given that land access is the result of both formal and informal decisions, land scarcity is strongly influenced by the broader concept of land governance, i.e., how influence and authority shape land outcomes. Practically, this can be conceptualised as a mixed land governance system, with simultaneous, coexisting top-down, bottom-up, and sectoral land architectures, each modifying, affecting, steering, and controlling the resulting land use, land rights, and land conversions. Such a complex system has implications for the sustainable longevity of land. One can view the conversion of land for UA as an instance of the complex land governance architecture, which in turn affects various types of land scarcity. These types of land scarcity ultimately result in outcomes which are sustainable or not. Land governance and sustainability should thus be seen as a Nexus. Within this complex land governance architecture, one stakeholder group is local communities, which advocate for civic ownership to buffer against land insecurity and policy discontinuity.

3. Materials and Methods

This article relies on a city-by-city analysis comparing the experiences and results of UA and developments in land scarcity. The experiences and results are drawn from documented evidence, including the Bureau of Statistics (BPS) operating within the city administrations, as well as municipal agency reports and academic articles on UA using remote sensing. Notably, city-wide UA statistics are rarely published as a single statistical area figure. Instead, one needs to extract and infer these by interpreting and assembling land cover and land use data from small household plots, rooftops, and community gardens, rather than by identifying consolidated areas designated or specifically recognisable as UA. The consequence is that statistical precision varies across cases, as most available data is fragmented and most cities use their own measurement standards, units, and methodologies. Therefore, the best possible and available data can be derived despite gaps in data quality.

The cities in Indonesia include Bandung, Jakarta, Makassar, Semarang, Surabaya, and Yogyakarta (in alphabetical order). Chronologically, Surabaya has the longest-running UA program, which has been running since 2009 and has gradually established different projects throughout the city, targeting low-income families by providing yard-based cultivation. The other cities started their UA as pilot programs through either public initiatives, such as the P2L, or through specific NGO-supported projects or private company projects [19]. In most cases, UA began as grassroots community initiatives in response to urbanisation challenges, a lack of green spaces, and the need for food, but later evolved into more formal government programs. Such community programs typically started by using rooftops, small yards, and narrow spaces to grow food and using simple technologies, such as hydroponics and vertical farming [20]. This is often represented in literature as practical bottom-up solutions to urban pressures.

The data analysis and interpretation follow a critical cross-cutting synthesis, focusing on several key aspects:

• The effectiveness of the P2L program. The key method for interpreting the effectiveness of a policy is a summative evaluation [21]. This interpretation draws on a realist evaluation [22] that focuses on understanding the links between context, mechanisms of reasoning in the design and implementation of the policy, and outcomes.
• The land scarcity spectrum. This part of the interpretation focused on comparing changes in land-use areas to assess changes in the different types of land scarcity. The aim is to judge whether there is a connection between the extent or type of UA areas and the degree or type of land scarcity. A particular focus is on the extent of green areas as a proxy of changes in areas for UA.
• The governance architecture and resilience.

4. Results

The findings are discussed in the subsequent sections for each city.

4.1. Bandung

Buruan SAE (https://buruansae.bandung.go.id/) is an integrated urban farming program promoted by the Food and Agriculture Office (in Indonesian: DISPANGTAN) of Bandung city, aimed at addressing the food-related problems in Bandung [23]. It involves using and/or converting available yards or plots of land for gardening to meet the family's food needs. In addition to these government-supported programs, there are grassroots initiatives that are amplified through partnerships with Universitas Padjadjaran. The number of UA projects since the launch of the Buruan SAE in 2020 is 234. The Buruan SAE locations have spread across all kelurahan (urban villages). Of these, 100 received government stimulus funding, while 134 are community-initiated replications³ The agricultural techniques used here are vertical and micro-plot, which are more developed. Purnomo, Sitepu [24] show that community-led approaches outperform state-led, directed ones, and that civic ownership is the strongest predictor of UA resilience, but the absence of formal policy integration leaves programs vulnerable to land-use reclassification/reallocation and (real estate) development pressure.

From a land perspective, the city area of Bandung is approximately 16,730 hectares (167 km²), whereas the Bandung Metropolitan Area (BMA) is approximately 300,000 ha. Within this urban space, the agricultural land available in Bandung City totals only 807 hectares, and this continues to decrease due to land conversion for non-agricultural development. The green space in the form of urban forest areas covers only approximately 339 hectares (less than 10% of Bandung's area based on Landsat 8 analysis - [25]), well below the 30% RTH (Ruang Terbuka Hijau – Green Open Space mandate. Green space in Bandung's northern highlands (Kawasan Bandung Utara) has seen a dramatic decline: built-up land increased more than fivefold over 33 years, from 2,555 hectares in 1990 to 13,064 hectares in 2023, while green open space declined from 35,608 hectares to 25,100 hectares [26,27], with the highest reduction occurring between 2010 and 2015. The annual land conversion rate of built-up land in Bandung City reached approximately 137 hectares per year as of 2015 data [28].

4.2. Jakarta

The number of urban farming projects in Jakarta increased by about a quarter since 2019, with more than 500 community farms established in the city as of 2024 [28]. There are diverse pilots across districts, but they remain spatially and organizationally fragmented. Governance is also distributed and fragmented across various administrative structures, preventing the coherent land-use policy needed to achieve UA's sustainable benefits. The pilot areas remain islands rather than systems.

The administrative area of Jakarta (i.e., DKI Jakarta) covers roughly 66,000 hectares (662 km²) within the province, while the broader Jabodetabek metropolitan region covers more than 6,000 km². Regarding the amount of urban farming area, the total area of rice fields in Jakarta is approximately 600 hectares, owned by the private sector and spread across East, West, and North Jakarta [29] . Beyond rice fields, UA occupies approximately 21% of the total green space area in Jakarta [30]. Jakarta had approximately 10,008 hectares (9%) of green areas in 2013, compared to 33,467 hectares (29%) in 2007 [31] — a catastrophic loss of some 23,459 ha of green cover in six years driven by commercial and residential development. Recovery has been slow.

Land use changes were initially rapid between 1990–1995 and then more gradual through 2010; built-up land was identified as an active gainer in all intervals except 2010–2015. Unlike in previous intervals, annual changes were more uniformly distributed over time in 2010–2015 and 2015–2020 [32]. Green areas declined by 13.94% in the period 2000–2010 alone [33]. A great many of these changes are the direct result of real estate pressure [34], which also leads to higher prices and more competition for land [35]. From a land perspective, one could therefore argue that land is already scarce in Jakarta, so any further allocations for UA increase this scarcity. Moreover, the heavy real estate pressure competes with the UA plots. Tenure insecurity further undermines investment in ecological infrastructure.

4.3. Makassar

Urban farming in Makassar consists primarily of slum-based UA programs operating across multiple districts, with experimental plots such as the Sudiang kebun (garden). No aggregate UA area figure has been published for the city, but according to the city’s website, the Makassar City Government continues to show its commitment to promoting food self-sufficiency and community-based economy through the development of the Urban Farming program ⁴. The program was initiated by the Makassar City Fisheries and Agriculture Office (DP2) under the concept of an integrated, innovative area, with the development of two pilot Greenhouse Urban Farming sites.The two areas are in Barombong Village, Tamalate District, and Sudiang Village, Biringkanaya District. Both are designed as centres for UA education, production, and development, leveraging modern technology. The design of the Green House Urban Farming area includes various supporting facilities to enable integrated activities in agriculture, livestock, and fisheries.

The city area of Makassar is approximately 17,143 hectares (171 km²). Despite Indonesia's required minimum of 30% green open space, Makassar currently reaches only 9–12%, indicating a substantial deficit of 18–21 percentage points that contributes to urban heat, flooding, and declining air quality [36,37,38]. At an average of 10.5%, Makassar has only approximately 1,800 ha of green open space, compared with a legal requirement of roughly 5,143 ha. With regard to land use changes, the built-up land in Makassar is projected to reach 11,531 hectares (67.27% of the city) by 2031, up from lower levels in 2016, while the remaining non-built-up land will fall to 5,612 hectares (32.73%), [39].

Despite the government's legal mandate to ensure 30% green open space, only 9-12% of the space is actually green and open, indicating a clear ecological deficit. It is relevant that the UA is part of the green infrastructure policy here, and that the slum-based programs show notable community empowerment outcomes. From a land perspective, UA is a statutory land-use right/restriction rather than a program based on the discretionary spaces of local government officials. Moreover, one could argue that failing to meet the 30% ecological target creates moral and legal pressure. Nevertheless, the de facto urban expansion has eliminated agricultural buffer zones around the city, so alley revitalisation and rooftop farming are responses to agricultural land scarcity, but still effectively reduce the total available agricultural land. Rooftop farming, however, is an active policy aimed at reducing the impact on land.

4.4. Semarang

Urban farming in Semarang has been active via the P2L (Pekarangan Pangan Lestari) program since 2015, and formalised its commitment further via the Semarang City urban farming program to promote food resilience, as part of the priority development issues stated in the 5-year medium-term development plan Rencana Pembangunan Jangkah Mengenah Daerah, RPJMD 2016-2021 [40]. There is no consolidated figure for the total UA area at the city level, but research studies reference 130 sampling farmers across multiple sub-districts in P2L program evaluations. The urban farming in Semarang has been diverse, including vegetables, cassava, sugar cane, durian, and mushrooms, whilst the technologies include aquaponics and hydroponics [41]. The success of the UA pilots was claimed too early, as the programs did not become embedded in regular policies. Moreover, from a land perspective, securing land tenure and land zoning still remained uncertain, leading to tenure insecurity.

The total city area is approximately 37,378 hectares (373.7 km²) according to [42], and 36,149 ha (2023) according to [27] Both data are collected from 2023 and reported in 2025, but apparently there is a slight difference. The annual growth rate of urban expansion in Semarang accelerated from approximately 2.7 km² per year (2005–2011) to 5.8 km² per year in the following period [43], which is roughly 270–580 hectares per year, are being converted to built-up land. Green space is decreasing in Semarang. Built-up land in Semarang increased from 2013 to 2022 by 8.84% —an area of 3,410 hectares —while green open space decreased by 7.59%—a loss of 2,928 hectares. Despite this, Semarang still nominally meets the 30% RTH threshold as of 2022 [44]. However, projections indicate that by 2032, green open space will fall to 29.62%, dropping below the legal minimum [44].

4.5. Surabaya

Surabaya's spatial plan for 2014–2034 targets a minimum land use change of 30% green open space [45]. Previous mayoralty programs developed Surabaya's East Coast (Pamurbaya) as green open space, covering 2,871 hectares for flood protection [46]. Built-up land has been gradually expanding, though Surabaya's green space has been better maintained than most comparable Indonesian cities. The UA projects in Surabaya have been active since 2009, targeting poor families through yard-based cultivation. They are distributed across its 31 kecamatan (districts). There is no exact number of individual project sites publicly available, but reportedly, there are hundreds of kampung sayur (vegetable village) units city-wide [47]. The strong reliance on local government support creates heavy dependence on municipal budgets. The measured gaps in economic uplift and poverty reduction suggest that the program has not evolved beyond subsistence farming.

The Surabaya city area reaches 33,206 hectares (332 km²) according to [48] and 29,950ha (2023) according to [45], who also report a land use conversion of 4269ha (2023). These figures are clearly different, but also rely on different measurement techniques. From the total urban area, the green open space (RTH) is reported to be 22% of the city area [48], i.e. approximately 7,358 hectares, exceeding Indonesia's national performance index of 20%, and capable of absorbing 642,794 tonnes/year of CO₂ [49]. However, the statutory target is 30%, leaving a gap of roughly 8% (~2,658 ha) ⁵. Land use changes in Surabaya are mostly dominated by changes in non-built land to built land, mostly to provide additional housing [50,51]. Vegetation areas and ponds were gradually converted into urban areas for residential purposes [51]. This left fewer and fewer spaces suitable for farming or aquaculture within the city boundaries. Moreover, the UA program targets yards and marginal plots. This inherently constrains upscaling to larger areas of the city and may ultimately increase households' tenure insecurity.

4.6. Yogyakarta

The Lorong Sayur (Vegetable Alley) program is governed by the Yogyakarta Mayor Regulation No. 128 of 2021. Implementation is concentrated in the districts of Umbulharjo, Danurejan, and Kotagede [52], among others, with farmer groups operating across most of the city's 14 districts. A consolidated project count is not publicly available, but multiple reports in digital media cover various urban farming initiatives in the city. Kampung Sayur Baussaran is an area in Yogyakarta that involves the community in implementing urban farming. This empowers citizens to create green open spaces in urban areas, improve food security, and establish a tourist village in the city centre to boost the community's economy. Nirmala [53] finds that the urban farming projects maximise the function of yards, walls, green open spaces, road walls and alleys as a medium of vegetable cultivation, and that actors who play an important role in the empowerment of urban farming are the government, NGOs, communities, farmers, companies, donors, activists, volunteers, and academics. Crucial for the success is that urban farming projects rely on existing social, institutional, economic, ecological, spatial, and natural conditions. Besides the primary objective of increasing food production within the city, the initiatives have secondary effects [54]. For example, the Bausasran Vegetable Village has become a tourist attraction ⁶. It is, however, important to pay attention to the sustainability of urban farming in the future, given that, in general, members of farmer groups are older [55].

The total city area reaches approximately 3,250 hectares (32.5 km²) — one of Indonesia's smallest provincial capitals by area. Agricultural land represents only 3% of the total area of Yogyakarta — roughly 97 hectares [56]. The Lorong Sayur program operates principally in alleys and strips of land that are not captured in standard agricultural land statistics. Earlier studies show that the total green open space in Yogyakarta reaches approximately 1,469 hectares, or 16.2% of the total urban area [57] — significantly below the 30% RTH mandate, leaving a deficit of approximately 13.8%. The built-up area in Yogyakarta covers around 85% of the total city area, and urban green space has halved within less than a decade [58]. The most drastic change occurred in Gedongtengen sub-district, where 59% of urban green space was lost between 2008 and 2015. The widest absolute decrease was in Umbulharjo, which lost approximately 117.9 hectares of green space — declining from 325 hectares in 2008 to 207 hectares in 2015.

Resuming, the Lorong Sayur (Vegetable Alley) is an internationally recognised micro-space innovation. There is high community participation rooted in culturally embedded food production. Nevertheless, this ecological creative response to land scarcity also reveals the land crisis. If land alleys become the primary frontier, then structural land reform becomes overdue. While the model is admirable, it may not be scalable without serious zoning reform.

Table 1 summarises the overall findings regarding the UA characteristics in each of the six cities.

Table 2 presents the area characteristics related to urban farming and the allocation of green spaces for each city.

5. Discussion

5.1. The Effectiveness of the P2L Program

The policy context and policy reasoning in which the P2L program was designed were to address household food security, improve food diversification and address high child undernutrition and development impairment, in particular in urban informal regions [67]. When evaluating the statistics and documentation for the P2L program across different cities, the program appears generally successful, particularly from a food production perspective. Available documentation showed that food availability, access, and production increased, and the nutritional status of, for example, sampled women-farmers' groups improved [68,69]. The program's effectiveness seems higher when local participation is strong, as the Yogyakarta and Bandung cases show. Nevertheless, regarding the links to outcomes, long-term sustainability projections and the continuation of the program when P2L budgets are no longer available, remain absent. [70] describes that in Yogyakarta, the program is quite sustainable ‘socially’, but less sustainable ‘economically’. The program struggles to deliver significant economic benefits and faces economic problems despite the strong community participation. So, while community participation is crucial, it is also a dependency variable.

5.2. The Land Scarcity Spectrum

Overall, across all cases, the size of the urban farming areas is negligible as a share of the city territory. Even in the best-documented case of Bandung, the UA area occupies only a fraction of the city and is declining. This reinforces the argument that one should perhaps measure tenure security rather than the size of the aggregate area. The figures in Table 2 do not show a linear correlation between the extent of urban farming areas and either the degree of land scarcity or the degree of UA success. One could perhaps argue that land scarcity itself might be a driver of innovation: in Makassar and Yogyakarta, where area constraints are highest, social and technical innovations also emerged. Besides the relatively limited area available for urban farming, the allocation of green spaces decreases across all cities and is generally below the target of 30%. While Semarang marginally meets the target, Makassar and Jakarta exhibit the most severe green-area deficits. Yogyakarta has halved its green space in under a decade. This not only shows the limitations in increasing urban farming areas (and hence the area-based land scarcity) but also the land scarcity from an ecological perspective (ecology-based land scarcity). Furthermore, the Surabaya cases show that the program targets yards and marginal plots without considering the loss or change in tenure security which this causes. An exception is perhaps the development of vertical and micro-plot urban farming techniques, which do not occupy a significant amount of land (tested in Bandung, for example), yet require additional water infrastructure. A decisive factor in assessing land scarcity in all its dimensions is therefore whether land access and tenure are institutionally secured or precarious.

5.3. The Governance Architecture and Resilience

The data make it clear that in terms of urban farming success, community-led programs consistently outperform government-directed ones. In Semarang and Surabaya, the government is the main driver of the programs, whereas in Bandung and Yogyakarta, the government has a more nodal role as enabler rather than active stakeholder. An explanation could be that bottom-up initiatives and civic ownership are independent of budget cuts, policy changes, new political narratives, and formal roles in land-use and zoning allocations. Such programs should thus be potentially more sustainable. Additionally, variations in city characteristics imply that a uniform policy design for each city generally does not work well. The land realities of the metropolitan region of Jakarta are quite different from the alley-farming characteristics in Yogyakarta. Hence, there is a need for a more diversified policy framework that allows for contextual and contingency differences.

Limitations of this study, and perhaps also of previous studies which used remote sensing as a tool for land use and land cover changes, are that mapping projects tend to focus on the physical characteristics of the conversion of land, and not so much on the inner characteristics of use and rights changes close to households, or on measuring area changes in connection with UA. Hence, the benefits of remote sensing for monitoring changes in UA remain limited. Overall, the data gaps are analytically significant. Publicly available consolidated figures on urban farming across all six cities are absent. How they relate to land rights remains complex, as cities do not formally allocate land to UA and don’t seem to systematically measure the areas or changes.

A recommendation for addressing these limitations is to recognise community agricultural land in urban zoning and coding. This will not only strengthen tenure security and recognise community initiatives, but also make the share of urban farming in the overall land-scarcity debate more measurable and visible. Makassar’s legal green space mandate could serve as an example or legal precedent, operationalised through urban farming-related land use or land tenure rights.

A second recommendation could be to integrate urban farming into city-level ecosystem services valuation (e.g. measuring and crediting carbon, cooling, biodiversity). This would not only provide a better assessment of value-based scarcity (usually based only on economic monetary values) but also provide better insight into ecological-based scarcity. Such a valuation would also strengthen the argument for protecting land or compensating for its loss.

A third recommendation would be to allow for more hybrid governance approaches. The cases of Bandung and Yogyakarta prove that formalisation can occur without bureaucratisation. The city government can play a more nodal role in securing land rights and providing resources, whereas communities could assume greater responsibility and accountability for the design and management of the UA projects.

6. Conclusions

In conclusion, regarding the main research questions, one could observe that the success and failure of UA initiatives in terms of food access, quality, and production do not directly depend on the degree or changes in land scarcity in the city. Urbanisation in itself causes land and property prices to increase rapidly. This makes it financially infeasible for urban farmers to buy or lease land for agriculture in cities or in their vicinity, as traditional farming cannot compete with the commercial or residential value of urban property. When urban farming is promoted, it generally increases land scarcity in all its dimensions. Not only does the loss of green areas, in all cases, create area-based, value-based, and ecology-based land scarcity, but the lack of active protection of tenure security in locations where UA programs occur also creates a general downward trend in land tenure security and, as a result, people-based land scarcity. Still, one needs to note that the amount of land allocated to urban farming is generally negligible compared to the agricultural land being absorbed by urban expansion, and negligible compared to the amount of built-up land being created within the city. Consequently, in terms of food production or food security – i.e. in terms of providing food to all urban citizens – is inot sufficient.

Given the effects on tenure security and the current insufficient production of UA, policy recommendations include recognising community agricultural land in urban zoning and coding, and advocating for urban farming in city-level ecosystem valuation. This can become possible if more hybrid governance approaches are stimulated or created. Nevertheless, more research is needed on the effectiveness and adequacy of these recommendations. This requires more longitudinal comparative mapping and data collection on land tenure as well as ecological changes and impacts. The data should also be regularly checked and compared to extract and analyse more unique or standard figures.