What Does Japanese Knotweed Look Like?

What Does Japanese Knotweed Look Like?

Identifying Japanese Knotweed

Would you be able to identify Japanese Knotweed in the grounds of a property? What if you are purchasing a house during the spring, how different would Japanese Knotweed look compared with how it looks in the summer?

Being able to identify Japanese Knotweed is perhaps a skill that could save you money (and a lot of heartache) when purchasing a house. But what does Japanese Knotweed look like throughout the seasons? Like most plants, Japanese Knotweed changes in appearance throughout the year. It will die off in the winter leaving brown dead stems but come the spring it will rapidly produce new shoots and leaves for the summer and autumn. Japanese Knotweed usually grows from around April to October and the plant is most easily identifiable during mid-summer, with bright green leaves and small white flowers. By looking at pictures of Japanese Knotweed throughout the seasons one can develop the ability to identify Japanese Knotweed, a useful skill when looking to purchase a property.

Japanese Knotweed – winter

Japanese Knotweed during the winter is identified by dark brown canes that are dying off and the plant becomes dormant. The canes decompose and are hollow and brittle. The leaves are brown and drop off at the stem.

Japanese Knotweed in the winter

Japanese Knotweed – spring

Japanese Knotweed can grow very quickly at the start of spring. The shoots can grow up to 3 metres and appear red or purple in colour with an appearance similar to small, red asparagus spears when they first begin to emerge.

Japanese knotweed in sprint

Japanese Knotweed – summer

During the summer Japanese Knotweed will be easier to identify. It produces one stem (or leaf stem) per node producing a zigzag pattern in the stem, bright green leaves and elongated clusters of creamy-white flowers that appear towards the end of August.

Japanese knotweed in summer

Japanese Knotweed – autumn

The leaves will begin to turn yellowish in colour. Some leaves will have yet to turn yellow and will maintain its green texture but some leaves will begin to turn yellow and begin to wilt.

Japanese knotweed autumn

Identifying the Japanese Knotweed Rhizome

Japanese Knotweed rhizomeIdentifying knotweed rhizome

As these pictures demonstrate, Japanese Knotweed can change considerably in appearance throughout the seasons. 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.

For help with identification please email your photos to info@knotweed.co.uk or call 0333 2414 413


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