Perennials & Ornamental Grasses

Detect and fight giant hogweed - how to protect yourself from the poisonous plant


Big, stunning and so dangerous - that's how the giant hogweed comes from. Serious skin inflammation can occur just by touching it. You can only protect yourself by recognizing the plant in good time and then fighting it.

Giant hogweed can be clearly distinguished from other hogweed species. Giant hogweed is a plant that originated in the Caucasus and has been spreading freely in Europe since 1950. Large parts of Austria have now been affected, but even in Germany it has long been safe from the poisonous plant.

Many social media are currently warning of the giant hogweed. And not without reason. Because the sap of the plant is extremely aggressive and only causes the slightest touch of severe skin inflammation.

What makes giant hogweed so dangerous?

As already mentioned, it is the plant sap that makes the giant hogweed so dangerous. However, the plant's toxic substances are only developed in conjunction with sunlight.

You have to imagine it like this: If the plant sap comes into contact with the skin, the protective coating of the skin is destroyed. If the sun shines on the affected area, severe burns can occur within 24 hours. Typical side effects are shortness of breath, circulatory problems, sweating and fever. Very often there are also oozing blisters, which often take several weeks to heal.

On particularly hot days, you don't even have to come into contact with the plant, it can be dangerous if you only come close to the plant, since the toxic substances (also referred to as furanocoumarins) are distributed in the air.

As you can see, the giant hogweed can only be "enjoyed" with great caution. Children in particular should be warned about the plant.

Where does the giant hogweed grow?

Similar to the allergy-causing ragweed plant, the giant hogweed loves little used areas. It is very often found on the edges of roads, forests and paths, but the poisonous plant can also be found on rivers and streams. And although they prefer fallow land, sooner or later they will find their way into the home garden. There they often settle on nutrient-rich soil. So keep your eyes open.

Recognizing giant hogweed - 4 important features

In order to protect yourself from the giant hogweed, it is of course important to know what the plant looks like and by what special features you can recognize it.

The giant hogweed naturally has a certain similarity to the meadow hogweed, especially when the giant hogweed is only in the early stages of growth. So that you can easily distinguish it, here are a few key features.

Feature 1: The size

Gigantic! The giant hogweed can reach a size between three and five meters.

For comparison: The meadow hogweed is only about 1.5 meters high.

Feature 2: The stem

The stem of the plant is like a stem. It can assume a diameter of up to 10 cm in the course of its growing season. He is also very hairy and there are lots of small red spots on it.

For comparison: The wild hogweed grows rather slim and has green stems throughout.

Feature 3: The flowers

The giant hogweed is also immediately noticeable in the area of ​​the flowers. It has huge umbels that bloom from white to light pink from the second year. Here too, the diameter is really gigantic with up to 80 centimeters. Apart from the size, the flowers are similar to the flowers of Giersch and Wilder Möhre.

For comparison: The plate-like flower umbels of the meadow bear claw only reach a diameter of about 25 cm.

Feature 4: The leaves

Hardly any plant has such huge leaves as the giant hogweed. The strongly pinnate leaves, which are very serrated, can be up to one meter long. To reach this size, you have to stand in a particularly nutritious place.

© TwilightArtPictures -
The giant hogweed is up to 5 meters tall

© Miket -
The flower umbels also reach a size of up to 80 centimeters

© Heinz Waldukat -
The reddish spots on the stem can be seen very well here

© GerardM At Nl.wikipedia, Via Wikimedia Commons
The giant hogweed has strongly pinnate leaves that can grow up to one meter long at a convenient location.

How to fight the aggressive plant

To protect himself and his children from the possible dangers of the plant, it is important that the giant hogweed is removed from the garden. Mowing alone will only help for a short time, as the plant will sprout immediately.

Do better:

First of all, it is important that you take control measures before the plant begins to seed. If the plant has scattered its seeds, the plant dies and lots of new ones grow in other locations.

" Little hint: An approximately 3 year old giant hogweed can scatter up to 50,000 seeds. The seeds also have special flight and swimming properties.

Preparatory actions:

Before you approach the plant, you should protect your skin with protective clothing. Make sure you also wear gloves and respiratory protection. It is also recommended that you take control measures on a sun-free day or in the late evening. This will minimize the risk of burns.

Fighting giant hogweed:

Tip 1: Separate the plant from the root

As already mentioned, simply mowing is not enough. It is much more efficient if you cut the plant over the roots. To do this, you have to dig a depth of about 10 to 15 centimeters into the ground with a spade, separating the root from the plant. Neither root nor plant can sprout in this variant. The best time to combat this is either directly after flowering between September and October or in spring between May and June.

Tip 2: Cut off the flower umbels

So that the plant does not spread any further, it can also help to simply remove the umbels between the flower and the fruit set. The only disadvantage of this variant is that the plant always creates new flowers, which you then have to remove in further steps.

After you have removed the flower umbels, you should either burn them directly or fill them into tear-resistant bags and then dispose of them.

Important! Do not throw the plant and plant parts on the compost, but dispose of them in a professionally managed large composting facility. Afterwards, be sure to clean tools and protective clothing immediately.

Tip 3: Regular checks

The respective cookie of the plant should not be neglected. Regularly check whether a new plant does not sprout again. The best time to check is spring.

" My advice: If you do not want to take the removal, you can also contact the responsible nature conservation authority in your area. Often, the staff will also help you with the removal in private gardens.

Children like to use the huge stem as a blowpipe, hide under the large flower umbels or use it as a decorative hat. This is extremely dangerous and you should therefore provide information in good time. Show you pictures of the plant from our picture gallery above and talk in detail about the possible dangers. If there should still be contact with the plant sap, wash the areas immediately with soap and water and cover the respective skin area with clothing and a cream with a high sun protection factor in the next few days. If there are any signs of skin irritation, you should urgently consult a doctor.