Kenya Early Discounted Bundle Trial
KEN -21 -1666Last modified on October 29th, 2025 at 12:04 pm
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Abstract
One Acre Fund (OAF) is an agricultural service provider that provides support for smallholder farmers in Africa to access agricultural inputs, training, and markets, to help the farmers increase their harvests and income. PAD and OAF began collaborating in 2016 on efforts to increase adoption of agricultural inputs and improve OAF operations in Kenya and Rwanda.
We conducted an Early Discounted Bundle (EDB) trial with OAF in Kenya during the 2021 long rainy season to test whether digital interventions alone could replicate the input adoption effects found by Duflo et al. (2011), particularly in contexts where farmers already have high familiarity with recommended inputs. The intervention targeted past OAF Duka shop clients and former core program members with an SMS campaign promoting hybrid maize seeds combined with fertilizers (DAP or CAN); the campaign offered time-limited digital discount coupons for bundled purchases shortly after the 2020 short rainy season harvest. A bundled input package is designed to ensure that farmers purchase the three complementary inputs in appropriate quantities for their land size.
While the trial did not increase actual bundle sales, it significantly boosted individual farmers’ input purchases and Duka shop engagement (they were 11.5–16.4% more likely to visit the shops) and moved purchase timing 2–6 days earlier. Treatment effects were strongest for maize hybrid seeds (16.2–19.1% increase) and DAP planting fertilizer (15.7–18% increase). We compared these findings to OAF's other existing discount program, Super Saver Discount (SSD), and found that in-person promotional strategies achieved higher bundle uptake than the digital-only approach. This finding suggests that, while digital-only campaigns are more cost-effective, in-person extension plays an important role in closing the adoption gap. -
Status
Completed
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Start date
Q1 Jan 2021
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Experiment Location
Kenya
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Partner Organization
One Acre Fund (OAF)
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Agricultural season
Long Rains
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Experiment type
Impact Evaluation
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Sample frame / target population
Potential clients of 4 well-established OAF Duka shops (Bungoma, Kabiyet, Malava, Yala)
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Sample size
16,170
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Outcome type
Input adoption
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Mode of data collection
Partner administrative data, Phone survey
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Research question(s)/hypotheses
1. Does an SMS campaign and a small, time-specific digital coupon increase the purchase of recommended input bundles?
2. How does the digital-only intervention (EDB) compare to a similar program (SSD) that uses in-person promotion strategies? -
Research theme
Communication technology, Input recommendations, Message framing
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Research design notes
We randomly selected four out of the seven established OAF Duka shops. The random selection of Duka shops was done with county stratification, which meant choosing one shop per county in Bungoma, Nandi, and Kakamega, and the shop of Yala in Siaya. The Duka shops that participated in the EDB trial were: Bungoma, Kabiyet, Malava, and Yala. The three out-of-sample Duka shops (Malakisi, Kapsabet, Ingotse), as well as other less established OAF Duka shops, were instead eligible for the SSD program that offered farmers slightly smaller discounts than the EDB discount. The EDB and the SSD discounts were for the purchase of a bundle of hybrid maize seeds and fertilizers; the bundles were designed with an optimal input ratio.
In January 2021, OAF identified a list of potential clients of the seven Duka shops. The list included two types of farmers: (a) past clients of the Duka shops, and (b) previous OAF core program members from sites that are near to those Duka shops.
The EDB study sample consisted of 16,170 potential clients of the four Duka shops: 13,040 were past clients of the four Duka shops, and 3,130 were former OAF core program members from sites that are near to the four Duka shops. The list of potential clients of the three out-of-sample shops comprised 12,159 past clients and 1,761 past core program members.
The farmers in the EDB study sample were randomized with stratification at the Duka shop level and the farmer type level (past clients or former core program members), and were randomly assigned to one of the following groups:
• Control group (C): 1/3 probability.
• Time limited discount group (T1): 1/3 probability; Standard message sub-group (T1-A): 1/6 probability; Rationale explained sub-group (T1-B): 1/6 probability.
• Long period discount group (T2): 1/3 probability.Treatment farmers received 7 to 9 SMS messages explaining the agronomic benefits of adopting planting fertilizer DAP and topdressing fertilizer CAN in combination with hybrid maize seeds. Treatment farmers were also offered a small, time-limited digital coupon to purchase the recommended inputs in a bundle designed with optimal quantities; this offer nudged farmers to visit the OAF Duka shops. T1 farmers were given a coupon with an expiration date of February 15, while T2 farmers were given a longer period to use the coupon until April 16. T1 farmers were further divided into two subgroups with different message framing. T1-A farmers received the standard messaging offering the coupon discount and nudging them to purchase the bundle of inputs. Messages sent to T1-B farmers also included the rationale for the recommendation to make purchases just after the short rainy season’s harvest, which was to encourage farmers to invest their income in agricultural inputs: “Invest in farm inputs when you have money now!” Control farmers were not sent any SMS message and did not receive a discount coupon to buy the bundle.
In the last two weeks of July, we conducted a qualitative phone survey about farmers’ input purchases and preferences. The survey gathered the feedback of 83 farmers, of whom 64 were part of the treatment group (77%), and 19 were part of the control group (23%).
For reference see Duflo et al. (2011)
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Results
OAF's discount coupon intervention significantly increased farmer engagement with Duka shops. Compared to control farmers’ average of 12.2%, T1 farmers were 2 percentage points (or 16.4%) more likely to make a purchase or visit the OAF Duka shops, and T2 farmers were 1.4 percentage points (or 11.5%) more likely to do so (T1 significant at p-value < 0.01 and T2 at p-value < 0.1). Administrative data shows significant increases in individual component purchases, and, importantly, in correct quantities. Farmers in T1 were 14.8% more likely to purchase individual bundle components in correct quantities and T2 farmers were 25.9% more likely, compared to control group farmers. While the administrative data suggest few purchases in bundles (only 0.1% uptake), farmer self-reporting in a follow-up survey suggests greater uptake in bundles. This may be due to over-reporting or how the purchases were recorded at the Duka shops as individual input purchases instead of bundle purchases.
The intervention effectively drove farmers’ purchases of maize hybrid seeds and planting fertilizer (DAP), with treatment farmers significantly more likely to buy these key inputs: T1 farmers were 19.1% more likely to purchase seeds and 15.7% more likely to purchase DAP, while T2 farmers were 16.2% more likely to purchase seeds and 18% more likely to purchase DAP. Additionally, treatment farmers made purchases significantly earlier than control farmers; the timing effect was most pronounced for DAP purchases (2–4 days earlier across treatment groups) and aligned with the expected urgency created by limited-time offers. The treatments’ impact on the purchase of top-dressing fertilizer (CAN) were also in the positive direction, but only statistically significant in the long period discount group (T2).
Although the potential clients of the SSD program did not visit OAF Duka shops more compared to the control farmers in the EDB trial, they purchased more bundles compared to both the control and treatment groups of the EDB trial. Moreover, they were also more likely to purchase CAN top-dressing fertilizer. The effectiveness of these in-person promotional strategies suggests that, while digital-only campaigns are more cost-effective, in-person extension plays an important role in closing the adoption gap.