Berlin is planting a million trees by 2040 – what’s behind it?

Berlin is planting a million trees by 2040 – what’s behind it?

On November 3, 2025, the Berlin House of Representatives passed the nation's first climate adaptation law, the TreesPlus Law. This groundbreaking law requires the capital to plant a total of one million new street trees by 2040 to increase resilience to heat, drought and heavy rain. Over 30,000 Berliners had signed for the law, which increased the pressure on MPs. What is particularly noteworthy is that after an initial rejection, the CDU and SPD turned around and voted for the law in order to forestall a potential referendum. A rejected law would have resulted in little less than a direct confrontation in climate policy, which would have made the issue more present in the election campaign. According to CDU parliamentary group leader Dirk Stettner, the early adoption of the law is a win for democracy.

The new law stipulates that all trees felled in the last ten years will be replaced by the end of 2027. From 2027, citizens will also be able to plant new street trees together with specialist companies. A binding set of rules will be introduced: From May 2026, the 1-to-3 rule will apply, which stipulates that for every tree felled, three new ones must be planted. Construction projects must be checked beforehand for their compatibility with climate adaptation goals. Around 170 “heat districts” are to be designated in particularly hot and sealed urban areas in order to create cooling islands. However, critics fear that money from the federal government's special funds could flow into an ailing infrastructure project. The estimated cost of implementing the law is around 3.2 to 4 billion euros.

Financing and monitoring

The comprehensive project could be partially financed through a special federal fund, although this has not yet been finally decided. For the years 2026 and 2027, 14 and 40 million euros have already been planned in the state budget. An advisory board will monitor the implementation of the law and provide regular reports to ensure that the climate goals are achieved.

The first trees are to be planted in two years, with primarily young plants being used. However, it takes about a decade for these trees to develop their noticeable cooling effects. Novel planting methods are also intended to help reduce costs, for example by using seedlings and root sprouts. The “Bauentscheid” initiative originally planned a referendum for 2026, which has now become obsolete because the law was passed in the House of Representatives.

At a time when climate change is becoming increasingly urgent, the TreesPlus Act sends an important signal. The measures are intended not only to benefit the ecological health of the city, but also to raise the population's awareness of environmental issues. While the effects of this bill on Berlin's landscape and the city's climate still remain to be seen, the example of Berlin shows what urban space and climate management can look like.