Tsurumaki Machi: Natsu Jikan

On the last day of school, Mitsuru, a primary school student who has the power to talk to plants waters a forgotten water hyacinth in his classroom. Since then, strange incidents start occurring in the town of Tsurumaki. A story of summer vacation in a nostalgic and warm world, drawn by a genius. (Source: Shinchosha, translated) Note: Contains an epilogue.