When walking by a pond or a slow moving river you will almost certainly encounter water mint (Mentha aquatica). It grows anywhere there is fresh water, indeed, anywhere the ground is usually damp. It is very common in Dorset where its preferred habitat exists flowering from July right through until October.
It is easy to identify this species as being mint, just take a leaf and have a sniff, all that is missing is the roast lamb! Water mint has this purple tinged green in the leaves like many of the labiate (or mint) family. The flowers are pale mauve and are formed around the top of the stem.
The leaves of water mint can be dried and used to make a herbal tea while the plant contains a chemical known for its beneficial properties in the treatment of deprerssion. So, if you are feeling down why not have a nice cuppa?