Common Valerian, is one of four species of Valerian found in Britain, the other three are Red Valerian which is often seen growing out of walls and is also sometimes white or pink! Then there is Marsh Valerian which is quite small, pink and as you would expect grows in wet places like fens and bogs. Finally there is one called Pyrenean Valerian, which I have never seen, possibly because it mainly grows in Scotland.
Common Valerian ( Valeriana officinalis ) is a perennial and as its name suggests quite common and found throughout the UK in woodlands along with some grasslands. The flowers which are out between June and August are white with sometimes a hint of pink. The buds are often pink but when the flower opens it looks white. The individual flowers are grouped into a small domed umbel. Usually the plant will have three groups of flowers at the top of the stalk, one larger cluster right at the top then two subsidiary groups which angle out a little lower down. As you can see in the photo below.
The individual flowers are composed of five petals which fuse together lower down to make a short tube. Very occasionally you get a flower made up of just four petals. They have a slight smell of vanilla.
The leaves are compound, being composed of several leaflets they are also quite jagged and arranged in pairs along the stem.
Valerian has an odd distribution in Britain, seeming to avoid the central spine of England. You find it in East Anglia, throughout Scotland and Wales, then along the Welsh borders and in the south west, but not often through the middle belt.
Valerian has long been ascribed various healing properties. It does contain a number of compounds which affect your metabolism. Whether in a positive useful way is not necessarily the case. Products extracted from the plant are commercially available. The most used product seems to be an oily extract from the root which may have some calming sedative effects. There is no connection between Valerian and Valium, which is not a natural product.