In spring
Look for red or purple shoots with tightly curled leaves, coming up from April. They grow fast — sometimes several centimetres in a day.
In summer
Tall, dense growth up to two or three metres, with hollow speckled stems that kink at each joint and broad leaves with a flat base.
In autumn
Clusters of small creamy flowers appear in late summer, then the leaves turn yellow and drop.
In winter
Only the dead canes are left — brown, hollow and brittle — but the rhizome underground is alive.
Often confused with
Bindweed climbs and twists round other plants. Dogwood has woody stems and curved leaf veins. Himalayan balsam has pink flowers and grows along rivers. A photo to us settles it.