The 3+30+300 Rule for Healthier and Greener Cities
The 3+30+300 in brief
Urban forests provide a wide range of essential benefits. Current global challenges, such as climate change, environmental degradation, and public health challenges (such as the recent COVID-19 pandemic), have resulted in increased awareness of the importance of urban trees and green spaces.
While situations will always be complex and different, and guidelines are not written in stone, NBSI’s co-director Cecil Konijnendijk launched a new rule of thumb for urban forestry and urban greening in early 2021: the 3+30+300 rule. This rule focuses on the crucial contributions of urban trees and other urban nature to our health and wellbeing, as well as climate change adaptation. It also recognises that we have to consider many different aspects of the urban forest in order to make it accessible to all. The rule or principle has as a key ambition to let urban forests and other green spaces percolate into all of our living, working, and learning environments. At the same time, it is straightforward to implement and monitor – and easy to remember. The rule of thumb provides clear criteria for the minimum provision of urban trees in our urban communities by setting the following three minimum requirements:
- 3 mature trees from every home
- 30 percent tree canopy cover in every neighbourhood
- 300 metres from the nearest high-quality public park or other green space
The 3+30+300 rule is already being used by hundreds of municipalities across the world. We at NBSI can advise you on implementation of the 3+30+300 rule, by supporting the development of policies and strategies but also through workshops, training, and inspirational talks.

The 3-30-300 Program
To better implement the 3-30-300 concept in your city, region, organisation or business, we, in March of 2022, offered an on-line program that discussed the concept in-depth and explained the different metrics and the evidence behind them. The program was led by Professor Cecil Konijnendijk, who, together with leading experts from the field, gave clear examples and recommendations on how the 3-30-300 concept could be implemented – and how it is being used already.
ThereĀ“s right now no decition made on if the program will be held again, but the full schedule of the 2022 program can be downloaded HERE