Rapid urbanization has led to an increased demand for food in urban areas. At the same time, land limitations and dependence on external supplies pose significant challenges to food security. Urban agriculture is an innovative solution for producing local food using limited land and modern agricultural techniques such as hydroponics, aquaponics, vertical farming, and rooftop gardens. This approach allows urban agriculture to be more resource-efficient, reduces distribution costs, and minimizes its environmental impact by lowering its carbon footprint. In addition to environmental benefits, urban agriculture also brings social and economic benefits by raising awareness of food sustainability, creating new business opportunities, and enhancing food independence in urban communities. This research uses a literature review method to examine various articles discussing the development, obstacles, and implementation of urban agriculture in different countries. The results show that urban agriculture makes an important contribution to improving food security while also providing a sustainable alternative for the global food system. Therefore, promoting the growth of urban agriculture from the perspective of sustainable food security requires support from government institutions, the private sector, and local communities.

Spinach (Amaranthus spp.) is a vegetable plant that is highly dependent on the availability of light and nutrients for its growth. Proper spacing plays an important role in influencing a plant's access to light and nutrients, which ultimately impacts its yield. This study examines the impact of planting distance on light and nutrient competition in spinach. Planting spacing that is too tight can lead to intense competition between plants, reduce the efficiency of photosynthesis, and increase the risk of etiolation in lower plants. On the contrary, planting spacing that is too wide reduces land use efficiency and increases the likelihood of weed growth. The ideal planting distance ranges from 15-20 cm between plants, which ensures maximum utilization of light and nutrients without resulting in excessive competition, thus supporting optimal growth and yield

Using organic fertilizer can increase soil fertility, which is crucial for plant growth. Another organic material source that may be utilized as fertilizer is water hyacinth (Eichhornia crassipes). The chemical makeup of water hyacinth was examined in this study, and the results indicated that its organic matter content was 78.47%, its organic carbon content was 21.23%, its total nitrogen content was 0.28%, its total phosphorus content was 0.0011%, and its total potassium content was 0.016%. It has been demonstrated that applying water hyacinth-based liquid organic fertilizer to corn (Zea mays) plants actually affects crop output. Utilizing water hyacinth not only improves soil fertility but also lessens pollutants in the environment caused by overgrowth in waterways. Water hyacinth can therefore be utilized as a sustainable and eco-friendly organic fertilizer option.

This study examines the main pests and diseases that attack cayenne pepper (Capsicum frutescens) plants grown in polybags. In Indonesia, this crop is in high demand for both household and industrial use. Nonetheless, farmers often face challenges from pest and disease attacks, including anthracnose, fusarium wilt and stem rot, leading to reduced yields. The methodology used was a literature review covering various sources related to cayenne pepper. Findings show that important diseases such as anthracnose can reduce yields by up to 80%, while pests such as fruit flies can cause chili fruits to drop prematurely before harvest. Effective pest and disease management is essential to increase the productivity of cayenne pepper cultivated in polybags.