Words meet photos: how green influencers' image-text congruence impacts user engagement

Purpose Green influencers play a pivotal role in encouraging sustainable behavior, often conveying their messages through multimodal content such as text and images. However, prior research has largely examined the effects of single-modality features (e.g. text-only or image-only) on user engagement, whereas the synergistic effects of image-text combinations remain underexplored. Design/methodology/approach This study investigates how image-text congruence in green influencer posts affects user engagement and the underlying mechanisms across four experiments. Study 1 leverages secondary data from real-world Instagram influencers to provide preliminary validation of the effect. Study 2 tests the effect of image-text congruence on user engagement. Study 3 investigates the mediating role of perceived novelty. Study 4 examines the moderating role of influencer type. Findings Across a secondary data analysis and three experiments, we identify an inverted U-shaped relationship between image-text congruence and engagement, mediated by perceived novelty. Moreover, this effect is moderated by influencer type: it emerges among micro-influencers but disappears among macro-influencers. Originality/value This study advances theoretical understanding of green influencer communication from a multimodal perspective and offers actionable implications for designing and disseminating effective sustainability-related content.