South Africa harbours many small-scale potato growers who produce for home consumption and local markets using variable levels of inputs (seed, nutrients, water). We assessed potato production practices, input resource use and use efficiencies, farm characteristics and yield gaps on smallholder potato farms in the KwaZulu Natal and Mpumalanga Provinces of South Africa through a survey and a crop model (LINTUL-POTATO-DSS). We explained variability in production practices and use efficiencies based on farm and household characteristics. The potato yields observed among smallholders in this study (on average 2.9 t fresh tuber ha⁻¹ in Mpumalanga and 6.8 t ha⁻¹ in KwaZulu Natal) were low, relative to the calculated water-limited yields (41.5 t ha⁻¹ in Mpumalanga and 24.5 t ha⁻¹ in KwaZulu Natal with optimal planting times) and to yields achieved by smallholders elsewhere in Africa. Input use heavily relied on government support and correlated well with yields. Farmers with low yields tended to have poorer resource use efficiencies, probably due to a combination of interacting yield-limiting factors. Enhanced access to irrigation is likely key to reduce the risks of investing in potato production, improve yields, and optimise planting times in relation to weather patterns and market prices. Timely access to fertiliser and clean planting material may further help to increase yields. The South African government aims to transform subsistence-oriented producers into small- to medium-scale commercially-oriented producers. The results suggested only a small proportion (18% or less) of the growers may have a potential to achieve this.

南非拥有许多小型马铃薯种植者，他们使用可变水平的投入物（种子，养分，水）供家庭消费和当地市场生产。我们通过调查和作物模型（LINTUL-POTATO-DSS）评估了南非夸祖鲁纳塔尔省和姆普马兰加省的小农马铃薯农场的马铃薯生产做法，投入资源利用和利用效率，农场特征以及产量差距。我们根据农场和家庭的特点，解释了生产实践中的差异以及使用效率。小农观察到的马铃薯的产量在这项研究中（平均2.9吨新鲜块茎公顷^-1姆普马兰加和6.8吨公顷^-1在夸纳塔尔）是低的，相对于所计算出的限水的产率（41.5吨公顷^-1在Mpumalanga和24.5吨^-1在夸祖鲁纳塔尔（KwaZulu Natal）播种，最佳播种时间）和非洲其他地区小农获得的产量。投入物的使用在很大程度上取决于政府的支持，并且与产量有很好的关联。产量低的农民往往利用较差的产量限制因素共同导致资源利用效率较差。扩大获得灌溉的机会可能是降低投资马铃薯生产风险，提高产量并优化播种时间（与天气状况和市场价格相关）的关键。及时获得肥料和清洁的种植材料可能会进一步帮助提高产量。南非政府的目标是将以生存为基础的生产者转变为以中小型商业为目的的生产者。