We live harmoniously side by side with most hogweed species. However, if giant hogweed (Heracleum mantegazzianum) comes into play, conflicts with humans and animals are inevitable. This guide informs you why the Hercules perennial is so dangerous and gives practical tips for combating it.
Why is hogweed dangerous?
The giant hogweed (Heracleum mantegazzianum) is dangerous because its phototoxic plant sap can cause burns on the skin. Sunlight in particular causes reactions such as itching, redness, blistering and, in the worst case, second to third degree burns, which are particularly threatening to people and animals.
Beautiful and extremely dangerous – interesting facts about giant hogweed
With its majestic shape and beautiful, white umbel flowers, giant hogweed cunningly deceives us about its danger to humans and animals. The following short profile gets to the heart of what makes the Hercules perennial so threatening:
- Growth height: 150 to 300 cm, rarely up to 400 cm
- White to pink flower double umbels: 30 to 50 cm diameter, 30 to 150 rays
- Flowering time: June and July
- Pinnate leaves: 100 to 300 cm long
- Hollow, hairy, red-spotted stem up to 10 cm in diameter
- Toxicity: phototoxic plant sap causes burns on the skin of humans and animals
Even a single giant hogweed produces myriad seeds, with the help of which the poisonous plant spreads invasively. As a result, more and more people, especially children, are coming into contact with the toxic plant sap. If sunlight falls on the wetted skin, severe reactions with itching, redness and blistering occur within 48 hours. In the worst case, second to third degree burns occur.
Remove hogweed professionally – tips for combating it
The best time to combat giant hogweed is in March and April, well before the flowering period. Please protect yourself from the toxic plant sap with overalls (€5.00 on Amazon), gloves, boots and a mask. Ideally, you deal with the floral aggressor when the sun is not shining.
Remove the Hercules perennial from the bed in stages. First cut off the above-ground parts of the plant. Then lift the rootstock out of the ground using the digging fork. The remains are not suitable for use in the compost heap, but should be completely destroyed or disposed of with household waste.
After 3 weeks, please check the infested area for renewed growth of the poisonous plant. In the following 5 years, the bed should be examined every early summer for offspring of the Hercules perennial.
Tip
In the wild there is a whole host of nasty plants that look very similar to hogweed. A prime example is the deadly poisonous spotted hemlock (Conium maculatum), the namesake of the legendary hemlock cup. In ancient times, the poisonous plant was used for executions and is still primarily associated with the execution of Socrates in 399 BC.
