During the early spring, around April to May, Japanese knotweed first surfaces, growing up to 2cms a day as it competes with less vigorous plants to establish a canopy to collect sunlight, forming dense stands of bamboo-like stems in the process. In spring new shoots of the bamboo-like plant emerge and quickly reach a height of two metres. One key characteristic is that you will notice little purple speckles on the surface of the stem. When looking to buy a property it is very important to be able to identify Japanese Knotweed and if you suspect that knotweed is present, you may wish to put a Knotweed Management Plan in place to deal with the problem and to satisfy most mortgage lenders. Japanese knotweed shoots appear in April with the white japanese knotweed flowers opening in July. As the spring fades and we move into summer, the stems of the Japanese knotweed will become thicker and start to resemble bamboo. Although the young leaves are hard to identify, the big clue to the plant's identity are the dead stalks from the year before. The other way to differentiate the two is the flowers. For information specific to the activity o… We place an encrypted cookie on your computer when you select 'remember password' when logging into your account. They resemble bamboo, are hollow, lightweight and have wooden-like stems. The difference is that this is a climbing plant so it will tend to be wrapped around garden structures and up walls rather than growing straight up out of the ground. Plants that people often mistake for Japanese knotweed include bindweed, Himalayan balsam, Russian vine, broadleaf dock and some lilac and woody shrubs. Even one rhizome remaining in the ground means that the plant will start to grow again and soon start to establish itself. Japanese knotweed (Fallopia japonica syn. Knotweed starts out as a reddish/purple shoot sprouting early spring time. You can customise your browser's cookie settings if you wish to manage your cookie security. Some species such as dwarf Japanese knotweed can have pink flowers but these are less invasive and their incidence in the UK is lower. How deep do Japanese knotweed roots go? The stems are green with purple flecks and Japanese Knotweed leaves turn from a yellow/brown colour in spring to rich green in summer. Hampshire, Romsey, Learn more. The stems will switch from a reddish-brown to a deeper hue of brown as it prepares for the dormancy of winter. What do the flowers of Japanese knotweed look like? Japanese knotweed (Reynoutria japonica syn. What does Japanese knotweed look like in April? Himalayan knotweed can have white or pale pink flowers. At certain stages of its lifecycle, Japanese knotweed will have red or reddish-brown stems that look similar to bamboo. Bindweed has largish white or pink trumpet flowers while knotweed has clusters or clumps of small creamy flowers. Japanese knotweed flowers are fairly distinctive. If the area hasn't been treated, often previous year's decomposition can be seen underneath. In late spring, canes can reach up to 3 metres (10 feet) high. You know it’s not a good thing, but what should you do? During March to April, the plant sends up new shoots, red/purple in colour with rolled back leaves. Japanese knotweed shoots look a bit like bamboo stems but there the visual similarity ends. The Japanese knotweed plant (Fallopia japonica) tends to grow in clumps and can grow up to 13 feet tall in the right conditions, but is often smaller than this. What if you are purchasing a house during the spring, how different would Japanese Knotweed look compared with how it looks in the summer? Many plants such as bindweed and broadleaf dock have similarities in leaf shape and growth and often get mixed up. That its roots can grow quickly, getting out control in a short time fallopia japonica & cuspidatum. 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