The Brussels Flora Atlas 2024–26 is currently underway. This study outlines its objectives, methodology, current progress, and preliminary findings. Funded by the regional administration, the project aims to compile a comprehensive inventory of spermatophyte species occurring spontaneously in the Brussels-Capital Region and to map their distributions.

By comparing the results with previous atlases – the earliest from the 1940s and the most recent from 2006, which were based on a standardized grid system (IFBL) covering the entirety of Belgium – we can assess changes in species ranges over time.

This edition is the first to incorporate a citizen science program, involving more than 110 trained volunteer botanists participating in field surveys. Data are entered via a dedicated platform, preferably using a smartphone app. Although field surveys will continue until October 2026, preliminary results already indicate the presence of several species not previously recorded in the Brussels-Capital Region, the majority of which are alien or non-native .