Preliminary Evaluation of High-Diversity Herbaceous Seed Sowings in Different Substrates

Seed-sown wildflower meadows are becoming increasingly important in our cities. One of the best methods is to design low-maintenance green spaces with an ecological approach. They can be used either to create perennial beds or to enrich and replace larger areas of regularly mown grass. Seeded surfaces are closer to a functioning ecosystem. The seed mixtures available in Hungary include seeds of native and non-native species, but due to a lack of time or resources, they have not been tested and have been in the field almost immediately. With our research, launched in autumn 2023, we tried to fill this gap and established seed-sown perennial beds in Budapest (Hungary), in ten plots in different media, using a seed mix of native species (96 taxa). Our experiment is an attempt to answer the question of what makes a seed-sown herbaceous plantation successful in the long term in an urban environment. Which species will emerge first, in which medium and which will persist in the long term? What will be the cover, diversity of the plots, the phenology of each species at different times of the year and to what extent does this depend on the medium and the frequency of irrigation? Which taxa will appear in each growing medium, and will there be taxa that can only develop in certain media? The study reports on the first experiences of the long-term study, according to which there were dynamically developing stands, but we observed a basically negative correlation between rapidly developing media and diversity. The most diverse species set was provided by the andesite aggregate medium, followed by green roof substrate, then demolition rubble with sand and sand.