<p>Food insecurity is a major issue in developing countries, and the set-in of COVID-19 complicated the issue. This led to people sensitizing themselves and putting in place a mechanism for coping with such shocks in the future. Embarking on household garden agriculture could be an important strategy in this regard. Despite the vital role household garden agriculture can play in household food security, there is a dearth of information on its effect on household food security, especially during health shocks like COVID-19. Hence, we explore the effect of household garden agriculture on household food security in Nigeria. Data were collected from randomly selected 480 households. We employ the USDA 18 Food Security Core Module and ordered logistic regression to realize the aims of the study. We find that the motivating factors for households’ engagement in household garden agriculture are to be food secure, to increase household food availability due to their experience from the COVID-19 lockdown, to improve household well-being, to eat fresh food, and to reduce household food budget. The level of food security is higher among households that engage in household garden agriculture (49.17%) than those that do not (18.33%). Thus, households that did not engage in household garden agriculture had a high level of food insecurity. The regression results further show that household garden agriculture significantly increased households’ food security. This study recommends the promotion of household garden agriculture among households to lower food insecurity by the government through the provision of microcredit dedicated to household garden agriculture.</p>