Bedding plants

Poisonous weeds - 9 varieties from mild to very dangerous


The plants do not show whether weeds are poisonous. For your own protection, nature and garden lovers should know and especially avoid poisonous weeds.

© Ruud Morijn -

For some, it is a matter of course that plants belong to the ecosystem of a garden, for others it is a nuisance from which no beauty can be won. Weeds separate minds, but should not be taken lightly when it comes to poisonous varieties. Our overview shows which “weeds” can sometimes massively damage your health.

© Anastasia Tsarskaya -

11 creeping ranunculus (Ranunculus repens)

Creeping buttercups (Ranunculus repens) spread very quickly, especially if the weeds get enough water (rain). Its creeping runners make it a thorn in the side of lawn lovers in particular. The creeping buttercup blooms from May to September and also spreads itself during this time (seeds). The herb is considered slightly toxic, but you should still wear gloves when fighting it.

Creeping buttercups are toxic to both humans and animals. The herb must not be consumed and skin contact should be avoided.

Valid active ingredients: protoanemonin
Consequences of poisoning: Skin irritation, blistering, nausea, vomiting

1. Creeping buttercup (Ranunculus repens)
© TwilightArtPictures -

22 Giant hogweed (Heracleum mantegazzianum)

Giant hogweed, also known as Hercules perennial, can be used as an underplant, but is generally considered a weed. The reason for this is the rapid spread and above all the fact that the Heracleum mantegazzianum displaces other plants. The beekeeper is delighted by the numerous flowers, but hobby gardeners try to fight the perennial by all means.

The most toxic thing about hogweed is the escaping plant sap, which is particularly associated with sunlight full dose unfolded.

Toxic active ingredients: furocoumarines
Consequences of poisoning: Itching, reddening of the skin, burns, blistering

2. Giant hogweed (Heracleum mantegazzianum)
© Marc Toutain -

33 Ambrosia (Ambrosia artemisiifolia)

Ambrosia is not a common weed poison, but should still be mentioned in this list. The mugwort, ragweed, ragweed or wild hemp plant, which comes from North America, is spreading more and more in Germany and does not stop at private gardens. Ambrosia is one of the most common allergy triggers during flowering from July to December. To date, there is no obligation to notify in Germany, however, finds of the poisonous weeds should be reported to the local green space office.

Toxic active ingredients: Trigger: pollen
Consequences of poisoning: allergic asthma, hay fever, conjunctivitis

3. Ambrosia (Ambrosia artemisiifolia)
© Backpackzio -

44 St. Jacob's herb (Jacobaea vulgaris)

Jacob's ragwort, also known as toad herb, spider herb, herb herb and Jakobs-Greißkraut, does not place any special demands on the soil. The main flowering period - recognizable by the striking yellow flowers - is in summer, but can extend into October. The herb is particularly troublesome for horse owners and farmers - because of its high toxicity. However, scarlet herb is not only found on meadows and on field boundaries, it can also spread in natural gardens.

Toxic active ingredients: Pyrrolizidine (alkaloids)
Consequences of poisoning: Liver damage to humans and animals, carcinogenic

4. Jacob's herb (Jacobaea vulgaris)
© Volodymyr -

55 The black henbane (Hyoscyamus niger)

The black henbane belongs to the nightshade family, can grow up to 60 cm high and shows a dark yellow, almost dirty flower in the months of June to October. The black henbane is not only poisonous, it also has a very unpleasant smell and is therefore not particularly popular with garden owners. The black henbane grows particularly well on a nitrogenous soil, on paths and on walls. All parts of the Hyoscyamus niger plant are poisonous, but especially the seeds and roots.

Toxic active ingredients: Hyoscyamine and scopolamine
Consequences of poisoning: racing pulse, loss of consciousness, death

5. The black henbane (Hyoscyamus niger)
© Элис -

66 Common Datura (Datura stramonium)

The common thorn apple or white thorn apple can grow to heights of up to 2 meters. The plant owes its name to its prickly capsules, which are formed from flowering between July and October. The latter smells sweet, but the smell of the stems and leaves is generally perceived as unpleasant. The common thorn apple grows preferably on the side of the path, but also on garbage sites. All parts of the common thorn apple are poisonous, but especially the roots and the seeds.

Toxic active ingredients: L-hyoscyamine, L-scopolamine, atropine (alkaloids)
Consequences of poisoning: Skin irritation, nausea, vomiting, confusion up to intoxication

6. Common thorn apple (Datura stramonium)
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77 Spotted Hemlock (Conium maculatum)

The spotted hemlock is a two-year herbaceous plant that likes to grow protected on hedges and fences. The Conium maculatum prefers a nutrient-rich clay soil and is almost unmistakably recognizable by its smell reminiscent of mouse urine. The hemlock (all parts of plants) is considered highly toxic in Germany and can even be fatal to humans.

Toxic active ingredients: Pseudoalkaloid Coniin
Consequences of poisoning: Burning mouth, gagging sensation, visual disturbances, muscle spasms, respiratory paralysis

7. Spotted hemlock (Conium maculatum)
© M. Schuppich -

88 Common Soapwort (Saponaria officinalis)

The common soapwort can grow to a height of up to 80 cm, even with this poisonous weed the flowering period is from June to October. The common soapwort is often found on the side of the path, the plant is satisfied with a sandy or stone floor. As can already be seen from the name, the soapwort was previously used as a detergent substitute. Today it still occurs in some medications, but you have to know that the common soapwort in high doses is fatal. The soapwort must not be eaten raw.

Toxic active ingredients: Protein toxin saporin
Consequences of poisoning: Nausea, vomiting

8. Common Soapwort (Saponaria officinalis)
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99 Common Easter luke (Aristolochia clematitis)

The common Easter luke is also called the upright Easter luke because of its growth habit. The plant, commonly known as weed, can grow up to 100 cm high, but the axis is creeping. In our latitudes the plant shows light yellow flowers from May to June. In ancient times the common Easter luke was used as a medicinal plant. Today you should leave that as possible, because both roots and leaves are considered poisonous.

Toxic active ingredients: aristolochic
Consequences of poisoning: Stomach ulcers, kidney-damaging, cancer-promoting