The purpose of this qualitative study was to describe the verbal interventions produced by teachers to support pupils' development of orthographic knowledge through invented spelling in three research-based intervention conditions: conventional (C condition), proximal (P condition), and progressive complexification (PC condition). We recorded six kindergarten teachers from Quebec and their 98 French-speaking kindergartners as they produced invented spellings in small groups. We then carried out an inductive thematic analysis of the teachers' verbal interventions (N = 1777). Results revealed four categories (with subcategories) of interventions, which mainly involved phonology and graphemes. Interventions concerning strategies for creating or memorizing spellings were observed less frequently. These results are discussed in the light of research on the impact of invented spelling.