Weld (Reseda luteola) is a tall, hairless biennial plant found on dry ground. It grows up to 1.5m tall and has green-yellow flowers. It thrives in disturbed soil and is a sign that we are near a path, track, railway, road or field edge.
As you can see in these pictures it points strongly towards the light and in open areas can indicate south. (In the first photo, above, we are looking West.) However, it does track light and the direction it points changes over the course of the day, an effect known as heliotropism.
It is also known as dyer’s rocket or dyer’s weed as it has been used as a traditional source of a bright yellow dye colour. It has been cultivated since Neolithic times for this reason.
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