The carbon impact of construction materials, such as Portland cement, plays a major role in greenhouse gas emissions. Additionally, the growing demand for air conditioning, caused by rising temperatures due to climate change, intensifies these emissions. In this context, biosourced materials with low carbon binders can be a promising solution. This paper presents an exploratory study on the potential use of reed as a bio-based aggregate for the production of agro-concretes with good mechanical strength while keeping interesting thermal properties. In particular, encouraging results were observed regarding the thermal behavior, showing a conductivity of around 0.1 W/mK for a density of approximately 1000 kg/m3. However, a better understanding of the reaction processes between the reed and the concrete was found necessary to develop formulations that optimize also mechanical behavior. For that purpose, Vicat test was carried out using either pure water or reed leachate. Results underlined a slight delay in setting of the studied cement. These promising preliminary results pave the way for a more in-depth study, with the aim of optimizing the reed concrete mix design.