Within the urban environment, urban agriculture faces myriad of challenges ranging from type of practices employed, through to production systems, to quality and safety of produce. An investigation was done to characterise urban agricultural farming practices and spatial nature of production systems within Nairobi city in the period between August 2013 and December 2013. The target was the active urban farmers identified through purposive sampling with the help of agricultural extension officers. Data was collected using sensitisation workshops, interviews, semi structured questionnaires and observations. The most common crops among active urban agriculture practitioners in order of prevalence were exotic leafy vegetables, fruit vegetables, herbs and spices while cereals and pulses are the least common. About 30% of surveyed farmers had plot sizes of between 0.125 to 0.25 acres. With respect to yield, over 65% of the farmers identified production technologies and space as the most critical issues affecting crop yields and wanted a review of urban and peri-urban agricultural policy About nine different production technologies were identified over the eight study districts most of which were directed towards space optimisation. The most common were green house tunnels, multi-storey garden, moist gardening and micro gardens.