Second urban Crošnjica in Croatia is planted in Zaprešić

Photos by Roman Avdagić and Igor Pavlović

A new urban “Crošnjica” mini-forest has been planted in Zaprešić as part of a growing Croatian environmental initiative aimed at improving urban ecosystems, boosting biodiversity and tackling climate challenges.

The project, led by the Croatian Scout Association and creative agency HEARTH, saw around 100 volunteers come together on 25 April, marking Earth Day, to plant the country’s second urban Crošnjica. The site, located in the grounds of Ban Josip Jelačić Secondary School, is the largest of its kind so far.

Spanning 400 square metres, the mini-forest includes 387 plants from 22 different native species. Designed to mitigate urban heat island effects and create more favourable microclimatic conditions, the planting also aims to improve air quality, reduce noise and support local wildlife.

The Crošnjica project began in May last year with a pilot “honey forest” in Kamanje, followed by the first urban Crošnjica planted in October at Ljudevit Gaj Primary School in Zaprešić. The latest addition represents a significant expansion in scale and ambition.

Crošnjica forests are compact green spaces, typically between 250 and 500 square metres, made up of multiple layers of native vegetation including trees, shrubs and ground cover.

They are planted using the Japanese Miyawaki method, which involves dense planting of diverse species to accelerate forest growth and resilience.

This approach results in self-sustaining ecosystems that require minimal maintenance while offering high biodiversity and improved resistance to environmental stress.

Beyond climate mitigation, the Zaprešić Crošnjica is expected to support a wide range of plant and animal life within a small area. It will also play a role in capturing dust particles and pollutants, contributing to improved public health.

An important aspect of the project is its educational value. Students will use the site as an outdoor classroom, learning about plant species and observing ecological processes that would normally take decades to unfold in nature.

Soil samples were taken before planting in collaboration with the MUZZA association, which focuses on science and sustainability education. Ongoing analysis will contribute to a scientific study examining the forest’s ability to absorb heavy metals, pollutants and carbon dioxide over time.

The planting brought together students, teachers, scouts and volunteers, including around 50 employees from dm – drogerie markt Croatia, the project’s main sponsor. The initiative forms part of dm’s 30th anniversary activities in Croatia, underlining its focus on sustainability and community engagement.

Local authorities also supported the project, with the City of Zaprešić assisting through its municipal services. Officials expressed hope that more Crošnjica sites will be developed in the area.

Organisers say the Crošnjica project will continue to expand across Croatia, with plans already in place to plant around ten additional sites in the near future.

Developed in collaboration with forestry and agronomy experts, the initiative builds on previous successful environmental projects led by the same organisers, including large-scale reforestation and carbon offset programmes.