The rock garden’s reputation precedes it: it torpedoes biodiversity, supports land sealing and harms the “city” ecosystem. Read on to find out why this is incorrect, why the difference between the terms rockery and rock garden is so important and what you can do to create an environmentally friendly rockery.

The rock garden’s reputation precedes it: it torpedoes biodiversity, supports land sealing and harms the “city” ecosystem. Here you can read why this is not correct, why the difference between the terms rockery and rock garden is so important and what you can do to create an environmentally friendly rockery.

It is considered the natural enemy of biodiversity: the rock garden or gravel garden. And yet they can be found in abundance in Germany’s cities – and above all in its suburbs and rural areas. Ulf Soltau in particular has brought the rock garden into the public eye. The biology graduate has been regularly posting new impressions of the so-called “gardens of horror” on his Facebook and Instagram accounts since February 2019. We have already reported on the gardens of horror here on G+L.de.

There you can see particularly ugly and therefore also quite impressive – supposed – rock garden examples. One “rock garden” stands out for its sheer barrenness, while the other “rock garden” reflects the full creativity of its designers. Here, the classic garden gnomes adorn the gray, small animal exhibitions amuse passing walkers or creatures from other worlds greet their owners when they come home.

Below we have compiled our current top ten gardens of horror.

Click here for the “Gardens of Horror” Instagram channel.

The rock garden at the center of a social conflict

However, the gardens of horror do not only take place in social networks. Ulf Soltau achieved a print media breakthrough with his book “Gardens of Horror”. He has since even published a second book, “Even more gardens of horror”. At the same time, the attention has led to actual changes in the building regulations of numerous local authorities. More and more local authorities are banning gravel gardens in new development plans.

For many people, the bans are important signs for the protection of species and against the increasing sealing of surfaces. Others see the ban on rock gardens and gravel gardens as an attack on their personal aesthetics and freedom of choice. They, the rock garden advocates, often opt for the gravel garden because of its supposed ease of maintenance and time savings. The rock garden has thus triggered a real social conflict in Germany.

The title “Noch mehr Gärten des Grauens” was published by Eichborn Verlag. You can order the book here.

For some years now, the rock garden has been surrounded by an extremely dubious reputation. However, this is not entirely true. Because the rock garden does not always have to be gray. First of all, a brief but important piece of information about the term “rock garden” itself. The examples shown above may be rock gardens. However, the type shown can be more accurately described as a “gravel rock garden” or “gravel garden”. Why is this so important? Well, while a correctly laid out rock garden can be an oasis of biodiversity, a gravel garden is – quite deliberately – the exact opposite.

The gravel garden: Only supposedly low-maintenance

So let’s first take a look at these gravel gardens. They are large areas covered with gravel, grit, pebbles or simply crushed stone, sometimes with decorative elements and sometimes with a few undemanding plants. The supposed ease of maintenance of such a gravel garden combined with its neat appearance is therefore the main motivation for those who create them.

Weeding, mowing the lawn, watering, spiders, ants and other insects – you hope to be able to save all this in the gravel garden in the long term. However, no matter how elaborately the gravel layer is separated from the subsoil by root barriers, the unavoidable entry of leaves, bird droppings and other organic material into the layer creates the best soil after just a few years, in which the first seedlings immediately begin to thrive. Over the years, mosses and algae also colonize those stones that are in the shade. To slow down this process, a gravel garden requires regular maintenance, for example with a leaf blower, high-pressure cleaner or scraper.

Ultimately, the process of renaturation cannot be stopped completely. The fissured surface of the gravel layer makes it practically impossible to remove all organic material from it every time during the cleaning process. Even with good maintenance, a gravel garden will no longer look as neat and clean as it initially did after ten years at the latest and, depending on the owner’s visual requirements, the gravel layer may need to be completely replaced and the root barrier renewed. If a gravel garden is not maintained at all, it may no longer be easily recognizable as such in less than three years.

Local authorities and federal states are increasingly banning gravel gardens

Gravel gardens are not only biologically largely lifeless areas. Due to their heat capacity and lack of evaporation, they also contribute to the heating and drying out of the urban climate. They also reflect sound to a greater extent than green spaces, making for a noisier city. Gravel surfaces are considered at least partially sealed in most municipalities due to their inadequate water absorption capacity. They are therefore subject to the obligation to pay rainwater charges. If the gravel garden is even separated from the ground by an impermeable layer of foil or concrete, it is fully sealed.

More and more municipalities are now imposing bans on gravel gardens for new development plans. Individual state governments also support this approach – including Baden-Württemberg, for example.

The rock garden as a biotope

Rock gardens created by skilled hands are structurally rich and species-diverse lean biotopes. They offer microclimates in which highly specialized plants, many of them from the Alpine region, feel at home.

There are several hundred species suitable for planting in rock gardens, which are characterized by their frugality and robustness. Some popular examples are blue cushion, cushion phlox, thyme, woolly cistus and gentian. In addition to a large number of insects that live in a near-natural rock garden, the best-known inhabitant of rock gardens is probably the strictly protected sand lizard.

You can find more information on particularly insect-friendly gardens (not just rock gardens) here.