Miyawaki Forests – An Article by Balázs Zsolnai

In many cities around the world, one can encounter a peculiar plant community created by humans, known as the Miyawaki forest. A few years ago, the first one sprouted in Budapest, specifically in Tabán, and since then, there are now numerous, precisely 12 such small forests thriving in Budapest and Baján. 

But where does this initially strange-sounding method come from, and what is its essence? 

Akira Miyawaki, who passed away in 2021 at the age of ninety-three, was the botanist who developed urban versions of forests based on his observations in the Far Eastern island nation. He created a system that mirrors large, perfect forests in a smaller urban format, operating on almost the same principles. The distinguished botanist and plant ecologist is associated with over one thousand three hundred mini-forests in Japan alone.

In the latter half of the last century, Miyawaki observed that Japanese forests often face fires, and that economically planted forests with pre-existing tree species are prone to easily catching fire and do not withstand the whims of weather. He studied cultivated forests, their species composition, and embarked on developing a method for urban mini-forests based on native species, which could be suitable for urban plantings in areas with polluted air.

The Miyawaki Method and Its Ecological Services

The Miyawaki forest is analogous to bonsais, where we create large and majestic trees in a size suitable for homes. In the case of mini-forests, we replicate the diversity of a large forest on an urban scale. We model the forest’s diversity in a small area. Many trees in a small space purify polluted urban air, provide shade, humidify and thus cool the environment, and offer a habitat and refuge for insects, songbirds, and mammals. 

The essence of the method developed in the 1970s is to plant as many trees as possible in a given area within cities, typically in areas with poor-quality soil.

Akira Miyawaki observed that if three or four saplings and shrubs are planted per square meter, the trunks of the trees may remain thin, but the competing plants grow incredibly fast and produce a lot of oxygen. 

The initial experiments proved successful, prompting several Japanese companies—such as Toyota—to ask him to establish mini-forests on their factory grounds. The method worked here as well, and more and more mini-forests began to sprout around the world, so today, Miyawaki’s name is associated with the planting of millions of urban trees using this method.

Planting

As with any method, there are certain aspects that should be adhered to in order to show respect for the creator. Deviations are possible, but in such cases, let us not call it a Miyawaki forest.

1. The soil composition must be examined, and either soil improvement or complete soil replacement must be carried out. This is essential, as it is one of the foundations for the healthy and rapid growth of trees, especially since the soil in urban areas is generally unsuitable for such plantings.

2. The indigenous tree species and shrubs of the surrounding areas must be assessed, and the species list should be compiled from these. Black-belt Miyawaki enthusiasts grow the plants from seeds themselves in pots at or near the future forest site.

It is important not to plant what we like, but what is native to the area.

3. The plants are to be planted in the prepared soil, rich in organic matter, in a completely random manner, thus mimicking nature. It is necessary to plant 2 or 3 trees and one shrub per square meter for the method to achieve its goals.

4. After planting and watering, there is one more important step: mulching the soil with organic material to a thickness of at least 10 cm. This protects the soil from drying out and provides nutrients to the soil during decomposition.

Straw is the most suitable material for this, which also serves as the most enjoyable conclusion to the work in an urban environment.

5. A low wooden fence can be built around the completed forest, benches can be placed, and a sign can be installed about the creators of the forest and what grows in the urban mini-forest.

Maintenance

In the 2-3 years following the planting, depending on the weather, it is advisable to water regularly during the summer months and occasionally remove larger herbaceous undergrowth or wheat sprouted from the straw, which can be left there as nutrients.

Later, the forest will become self-sustaining and a habitat.

Mini-forests around the world and at home

The Miyawaki method is popular in Asia and the United States.

In Europe, it is mainly spreading in France, Belgium, and the Netherlands, where, alongside public spaces, in school and kindergarten yards, concrete is being broken up and paving stones are being removed for mini-forest installations, thereby reducing the heat island effect while also conducting educational activities for future generations.

Hungary’s first Miyawaki forest was established in 2021 in the capital’s Tabán district. Experts from Főkert planted a total of one hundred and twenty tree saplings in an area of just forty square meters.

Among the planted species were serviceberry, hornbeam, wild pear, black locust, sessile oak, striped spurge, single-seeded hawthorn, as well as field and early maple. These species are typically native to the slopes of the Buda Hills, thus imitating the calcareous, deciduous forest community of the mid-mountain region.

The marketing of the first mini-forest proved so successful that small mini-forests began to sprout from the ground in several districts of Budapest and in a rural town, Baja.

These are, in order:

2. Baja Miyawaki 120 m2 400 plants

3. Soroksár Auchan 200 m2 600 plants

4. Boráros Square Miyawaki 60 m2 200 plants

5. Budafok Miyawaki 55 m2 200 plants. 

6. Lenhossék Street Miyawaki 80 m2 240 plants

7. Zsigmond Square Miyawaki 13 m2, 52 pcs

8. 2nd Baja Miyawaki 120 m2, 400 plants 

9. Andor Street Miyawaki, 60 m2, 240 plants

10. Rákoskert Miyawaki 260 m2 1300 plants

11. Erdélyi János Square Miyawaki 30 m2 240 plants 

12. Rákóczi Miyawaki 70 m2 280 plants

Balázs Zsolnai

certified horticulturist, plant doctor

+36705087070