Background Training women in home gardening and nutrition has been shown to increase household production and consumption of nutritious food and contribute to women's empowerment, but evidence is limited to short-term effects. Here, we investigate whether home garden support leads to long-term improvements in household nutrition and women's empowerment. To do this we use four waves of household-level survey data collected over a 7-year period (2013–2019) from an intervention (n = 395) and a

more »

... rol (n = 224) group in four rural districts of Bangladesh. We estimate the intent-to-treat effect using a difference-in-difference estimator. Results We find an immediate increase in the quantity of vegetables harvested from home gardens (+ 29.6 kg/year; p = 0.01) and this effect is sustained in years three (+ 42.3 kg; p < 0.01) and six (+ 37.0 kg; p < 0.01). The nutrient yield from the gardens also remained positive and significant, but the effect declined due to changes in the composition of vegetables. The effect on per capita vegetable intake, significant in years one and three, turned not significant in year six. Effects on nutrition knowledge, food preparation practices, and women's empowerment all remained significant in year six. Conclusions Home garden interventions in Bangladesh create sustained impact on a range of social, economic and nutritional outcomes. Refresher training after 5 or 6 years may help to maintain the full range of impacts observed.