The merits of three climate smart agriculture (CSA) technologies implemented by farmers were assessed in Machinga district of Malawi with respect to their soil quality and maize yield effects. Data were collected from farms implementing the three CSA technologies, namely conservation agriculture (CA), maize-pigeonpea (Maize-PP) intercrops and a local organic and inorganic soil amendment known as Mbeya fertilization (Mbeya-fert), from 2018 to 2019. With respect to resilience and adaptation, particulate organic matter, soil organic carbon (SOC), N, P, K, Ca and Mg all significantly improved while bulk densities were lowered under the three CSA systems. Higher annual biomass inputs and improved water infiltration from the Maize-PP intercrops were observed. With respect to productivity, CA and Mbeya-fert improved maize yields by 51 and 19%, respectively, compared to conventional farmer practices. With regard to climate change mitigation, increases in measured SOC in the top 20 cm depth compared to the conventional farmer practices amounted to 6.5, 12 and 10.5 t C ha −1 for CA, Mbeya-fert, and Maize-PP intercrops, respectively, over a period of 2-6 years. This suggests higher potential for carbon sequestration from CSA technologies. Furthermore, use of drought tolerant varieties, timely weeding and optimum plant populations, increased productivity. Improved gross margins from CSA practices were also apparent. Thus, employing these CSA technologies could enable farmers to be more resilient, productive and adapt better to climate change shocks leading to improved food security and livelihoods.

A study was conducted from 2014 to 2017 in Malawi to elucidate the short-term effects of maizelegume intercropping and rotation systems under conservation agriculture (CA) and conventional tillage (CT) on crop productivity and profitability. Twelve farmers hosted on-farm trials per district, in three districts, with each farmer having six plots. The design of the study was randomised complete block design arranged in a split plot fashion with tillage as main plot and cropping systems as subplots, with each farmer acting as a replicate. CA had 1400 and 3200 kg ha −1 more maize grain yield in the second and third seasons, respectively compared with CT. In the first two seasons, CT had 310, 180 and 270 kg ha −1 more cowpea, soybean and pigeon pea grain yields in Salima, Mzimba and Mangochi districts, respectively, compared with CA. Similarly, CA had 1100 and 950 kg ha −1 more groundnut grain yields than CT in Salima and Mzimba districts in the second and third seasons, respectively. Over the three-year study period, partial land equivalent ratio for maize ranged from 0.78 to 1.24. Largest net returns were achieved by intercropping maize with pigeon pea in Mangochi and rotating maize and groundnut in Mzimba and Salima districts.

Conservation agriculture (CA) is increasingly promoted among smallholder farmers of sub-Saharan Africa in a quest to improve food security while sustaining the natural resource base of the agro-ecosystems where agriculture is based. The aim of this study was to investigate the effects of CA and traditional tillage on soil organic carbon (SOC) and selected hydraulic properties in two contrasting agro-ecological zones of Malawi. Six farmers hosted on-farm trials in each location, with each farmer having the following treatments: CA with continuous sole maize (CA-SM), CA with maize–legume intercrops (CA-ML), and traditional tillage with continuous sole maize (CT-SM). Soil samples were randomly collected in October 2015, from farmers’ fields located in Chipeni, Chinguluwe, Lemu, and Zidyana where CA had been implemented for 10 years (2005–2015) at six depth intervals: 0–10, 10–20, 20–40, 40–60, 60–80, and 80–100 cm. Bulk density, soil water characteristics, and pore size distribution were determined using undisturbed core samples. At all sites, CA improved total SOC, carbon stocks, and the stable fraction of particulate organic carbon. Maize–legume intercropping under CA had 35%, 33%, and 73% more total SOC than CT-SM in Chipeni, Lemu, and Zidyana respectively. In Chinguluwe and Lemu, CA-ML had 0.54 and 0.50 g kg–1 respectively more stable fraction of particulate organic carbon (POMP) than CT-SM; whereas in Chipeni, CA-SM had 0.73 g kg–1 higher POMP compared with CT-SM. CA also improved soil porosity, pore size distribution, and water retention capacity by increasing the proportion of mesopores and micropores compared with CT-SM. Thus, changing management practices from CT-SM to CA has the potential to improve the soil organic matter and soil hydraulic properties across agro-ecological zones in Malawi, which is important for sustainable agriculture. Farmers should be encouraged to minimise tillage, retain residues as mulch on the soil surface, and practice crop rotation.

Integrated soil fertility management was promoted on-farm during the 2018/2019 cropping season in Thyolo, Phalombe, Mulanje and Zomba districts of southern Malawi, in purposively selected extension planning areas (EPAs). Sixty farmers, fifteen from each district were involved. Trials were established in farmers’ fields with smallholder farms as replicates and extension EPAs as blocks. The following were the treatments; Maize + 92 kg N ha-1 + 46 kg of P ha-1; Maize + 3 tons of compost manure ha-1; and Maize + 46 kg N ha-1 + 23 kg P ha-1 + 1.5 tons of compost manure. Grain yield data were collected at harvest. The data were analyzed in Genstat Discovery Edition 4 and were subjected to ANOVA at 95% level of confidence. Means were separated by the least significant difference (LSD0.05). No significant differences (>0.05) in Maize grain yields were observed between the treatment with Maize + 46 kg N ha-1 + 23 kg P ha-1 + 1.5 tons of compost manure and the treatment with Maize + 92 kg N ha-1 + 46 kg of P ha-1 in all the districts. Maize grain yields were significantly lower in plots treated with the full rate of manure (3 tons of compost manure ha-1) in Thyolo, Mulanje and Zomba district. Higher maize grain yields were registered in Phalombe (3,867-4,838 kg ha-1), followed by Thyolo (1,764-2,374 kg ha-1) and Zomba (740-1,120 kg ha-1). The trials confirmed that applying a combination of organic and inorganic fertilizer to maize, increase grain yields.

Low productivity characterizes the production of groundnut among smallholder farmers in Malawi. There is a need to explore options capable of increasing the productivity of the crop sustainably more especially under the changing climate. Against this background, experiments were conducted during the 2016/17 cropping season to investigate the potential to enhance the productivity of groundnut in Malawi through the combined use of inoculants (Graph-Ex and Histick-BASF) and foliar application of nutrients using Allwin fertilizer (legumes). The experiments were established at Bvumbwe and Chitala Agricultural research Stations and were laid in a randomized complete block design (RCBD) replicated four times. Data collected were analyzed in Genstat Discovery Edition 4 and were subjected to analysis of variance (ANOVA) at a 95% level of confidence. Means were separated by the least significant difference (LSD0.05). In general, foliar application of Allwin fertilizer alone particularly when conducted twice at two and four weeks after emergence produced a positive significant (p<0.05) groundnut grain yield response (97.8-170.8%) above the control. The yield increase is attributable to enhanced growth and development of the groundnut through the foliar supply of nutrients. In general, under the changing climate and amidst other constraints foliar feeding of nutrients using Allwin fertilizer alone particularly when conducted twice can increase significantly groundnut productivity in Malawi.