Please note: There is a risk of a fine: These are plants that are prohibited in German gardens

Which plants are prohibited in German gardens and why?

In German gardens, some plants are banned or strictly regulated for reasons of nature conservation, health or the fight against invasive species. Giant hogweed (Heracleum mantegazzianum), also known as Hercules, is invasive and spreads quickly. The sap can cause severe burns and allergic reactions when it comes into contact with the skin in combination with sunlight.

Japanese knotweed (Fallopia japonica) is also an invasive species. It displaces native plant species and can damage buildings and infrastructure due to its aggressive growth. The gland balsam (Impatiens glandulifera) is invasive and spreads rapidly along rivers. It displaces native species and can destabilize riparian vegetation. Giant reed (Arundo donax) is also invasive and can displace native plant species. The plant grows on banks and wetlands and contributes to soil erosion.

Poisonous plants such as belladonna (Atropa belladonna), monkshood (Aconitum) or foxglove (Digitalis) are highly poisonous and can cause serious poisoning if consumed or in contact with the skin. Such plants are especially problematic in gardens where children play. Ragweed (Ambrosia artemisiifolia) is a neophyte whose pollen can cause severe allergies and asthma. The exact regulation and prohibition of such plants may vary from state to state; information is available from the responsible environmental authorities.

Burkhard Bohne, born in Northeim in 1962, is a master gardener and since 1990 technical manager of the medicinal plant garden of the TU Braunschweig. He also works as a freelance author for various newspapers and garden magazines, is a Reiki teacher, author of various garden books and works as a garden planner with a focus on herb and vegetable gardens. In 2011 he founded the first herbal school in Braunschweig and in 2016 the Berlin herbal school. He lives with his family in Braunschweig.

What are the risks of growing prohibited plants in the garden?

There are plants that can cause serious allergic reactions, such as giant hogweed (Heracleum mantegazzianum) and ragweed (Ambrosia artemisiifolia). Consuming or coming into contact with the skin of highly poisonous plants such as belladonna (Atropa belladonna), monkshood (Aconitum) or foxglove (Digitalis) can lead to serious poisoning, which in the worst case can be fatal, especially for children and pets; risk.

Some invasive plants such as Japanese knotweed (Fallopia japonica) and balsam gland (Impatiens glandulifera) can spread quickly and displace native plant species. This leads to a loss of biodiversity and disrupts the ecological balance. The giant reed (Arundo donax), but also the Japanese knotweed, can destabilize the structure of soils and riparian areas due to its aggressive growth, which can lead to erosion and damage to infrastructure.

Planting prohibited plants may have legal consequences, including fines and requests to remove the plants. Authorities may require garden owners to remove prohibited plants, which often entails significant costs and effort. Many invasive plant species are extremely resilient and difficult to control. They also spread easily to adjacent properties, which can lead to significant conflict.

Are there exceptions or special permits for the cultivation of certain prohibited plants?

Yes, in certain cases there are exceptions or special permits for the cultivation of otherwise prohibited plants, especially if they are used for scientific, agricultural or other specialized purposes. Universities or research institutions can apply for special permits to grow prohibited plants for research purposes. These permits are often accompanied by strict conditions to ensure that the plants are safely controlled and handled to prevent their release into the environment.

In some cases, the controlled cultivation of invasive plant species for agricultural purposes may be permitted if they are necessary for the production of specific products. Here too, strict requirements and regular checks apply to ensure that the plants do not end up in the surrounding nature and cannot cause damage.

Some poisonous plants (e.g. foxglove) contain medicinal ingredients and may be grown under certain conditions. The cultivation takes place in specialized companies that are under strict supervision. Nurseries that specialize in the cultivation and sale of specific plant species can also obtain permits to grow otherwise prohibited plants under certain conditions. These companies must demonstrate that they can handle the plants safely and prevent their spread.

What should you do if you discover that you have a prohibited plant in your garden?

If you discover that a prohibited plant is growing in your garden, you must act quickly and responsibly to minimize potential negative effects and avoid legal consequences. First you need to be sure that it is actually a prohibited plant, because there are many plants that can look similar. If necessary, ask an expert for advice.

Learn about the specific regulations in your state or municipality, as regulations may vary. Environmental or agricultural authorities often have relevant information on their websites. Contact the responsible authority (environmental agency or nature conservation authority) to clarify how to proceed.

When removing certain plants, such as giant hogweed, it is important to wear protective clothing, gloves and goggles to prevent skin contact and injury. If possible, the plant should be removed with the roots to prevent it from sprouting again. With invasive species it is often necessary to also treat or replace the surrounding soil.

Prohibited plants may not simply be thrown into the garden compost or organic waste bin. They often have to be handed in in sealed bags at special collection points or burned. After removing the plant, regularly check the area where it was growing to ensure no new shoots appear.