At Helmrig we offer a wide range of treatment options to many invasive weed species
Effective treatment of a range of invasive weed species across North West England
In Europe the species is very successful and has been classified as an invasive species in several countries including the UK.
Japanese knotweed begins to grow in early spring and can grow in any type of soil, no matter how poor.
It can grow as much as 20 centimetres per day, and can reach a height of 1.5 metres by May and 3 metres by June. It does not produce viable seeds in the UK, but instead spreads through rhizome (underground root-like stem) fragments and cut stems. Japanese knotweed:
- produces fleshy red tinged shoots when it first breaks through the ground
- has large, heart or spade-shaped green leaves
- has leaves arranged in a zig-zag pattern along the stem
- has a hollow stem, like bamboo
- can form dense clumps that can be several metres deep
- produces clusters of cream flowers towards the end of July
- dies back between October and November, leaving brown stems
Himalayan Balsam is often found on river banks, growing up to 2 metres in height.
Each plant lasts for one year and dies at the end of the growing season.
- has dark green, lance-shaped leaves with jagged edges
- has reddish coloured stems
- flowers from June to October
- has large, brightly coloured flowers that are usually in variable shades from purple to pale pink
- can produce around 2,500 seeds per plant each year
- has explosive seed pods that can throw seeds over 6 metres away from the plant making it an extremely invasive plant.
You should take great care when identifying giant hogweed.
Contact with the plant, particularly the sap, can lead to severe blistering and scarring.
Giant hogweed closely resembles native cow parsley or hogweed. It can take four years to reach its full height of 3-5 metres and flower.
- has a reddish purple stem with fine spines that make it appear furry – like a stinging nettle
- has hollow stems
- has spotted leaf stalks
- has leaves up to 1.5 metres wide
- flowers in June and July
- has flower heads that are usually 50 centimetres wide – each flower head is capable of producing 50,000 seeds every year
- has seeds that can stay in the soil for several years before they develop
Australian Swamp Stonecrop
Forms dense rafts and outcompetes native plant species. Reduced light levels below the rafts can cause die off of waterweeds and algae and reduce water oxygenation levels.
The daisy-like, yellow flower heads of Common ragwort may be pretty enough to the casual observer, but they belie the poisonous nature of this plant. Renowned as a weed of paddocks and pastures, where it can be harmful to livestock, it is not usually such an issue in gardens or on waste ground. In fact, it is the foodplant of the black-and-red Cinnabar moth: sometimes its black-and yellow-barred caterpillars cover the plant, totally stripping the leaves. Common Ragwort is a biennial, flowering in its second year from June to November.
Common ragwort is a relatively tall-growing plant that has clusters of yellow, flattened flower heads, and leaves that look ‘feathery’ because they are very divided.
Buddleia is a popular garden plant that was introduced into the UK from China in the 1890s and has now become widely naturalised on waste ground, along railway cuttings and in urban areas. Its familiar purple flowers bloom from June to October and attract all kinds of butterflies and moths looking for nectar sources. Its winged seeds are dispersed by the wind and find it easy to colonise stony ground.
Buddleia is a very familiar bush, with large, drooping spikes of densely clustered, small, purple (or sometimes white) flowers. It has long, narrow leaves and the flowers have a honey-like fragrance.