Burdock Root has been used to help with the hair.  Dried burdock should be used by making a decoction (putting the herb in the water in a pot and boiling it down).

{snippet adszoo} It is thought to give a high shine to hair and contains biotin, copper, manganese, sulfur, Vitamins B1, B6, B12 and Vitamin E.

According to my notes on Burdock root, it is antioxidant, antiviral, antifungal and anti inflammatory. It's allegedly good for skin problems, although those statements have not been proven by the FDA.

Burdock root is said to contain calcium, phosphorus, zinc, silica, and selenium. It is though that burdock root is good for the hair, skin and nails.

Burdock is used by some people to fight toxins and to help purify the blood.   It stimulates sweating and has been used as a diuretic.  It also is thought to help regulate "inflammatory responses" which deal with the immune system.

Burdock root is thought to help stop hair from breaking by making it stronger.  And when hair is stronger, it can grow longer simply because its strong enough to be increasingly resistant to some of the styling done to it.

"Burdock is thought to work especially well on naturally curly, wiry or wavy textured hair such as is typical of women of African-American descent. Burdock root is also rich in phytosterols and essential acids, including the kind of long chain EFAs to grow hair to a long lengths."
http://www.vitaminsforhairgrowth.com/burdock-root-oil-for-fast-growing-long-hair/

You may have been introduced to Burdock Root through the awesome products at Qhemet Biologics.