Lavender
Lavendula officinalis. Syn. L. vera, L. angustifolia.
Family:
Lamiaceae, Mint family
Where to find this herb:
Originally from the western part of the Mediterrenean area. Now many varieties are grown all over the world.
Part(s) used:
whole herb
Special constituents:
Essential oil (up to 1%) containing linalyl acetate (up to 40%), linalool, borneol, camphor, limonene, and others.
Correspondance:
Mercury (Culpeper)
Uses:
Calming, vulnerary, antidepressant
Lavendel 
Lavendel Are you depressed, have you lost faith in life, can't you fall asleep at night? Then go to the Lavender. It is so powerful that one look at the tiny flowers should make all grief go away and make the joy return.
Exaggerated? Not really. Lavender is really powerful when it comes to depression and insomnia. Culpeper describes her as a Mercury-plant, but I feel there is something very motherly to her. She calms, balances, and cleans - insects stay away from her, she is pure as a virgin but not innocent - she knows the dangers of the world and how to deal with them.
The name lavender comes from lavare, meaning to wash. Maybe because of the wound-healing action of the plant, maybe because it is used in baths and soaps. Angustifolia means narrow-leaved; officinalis means it is a medicinal plant; vera means true/real.
The plant has a certain reputation for attracting partners. Cunningham states that is is best used to attract men - I guess if you use lavender as a perfume you will radiate purity and virginity rather than raw sexuality.
Closely related species:
Spike Lavender, Lavendula latifolia syn. L. spica. Good to keep insects away. The scent is stronger and more stimulating than real Lavender. Make little bags with this Lavender to keep away moths from your closet, and keep it smelling nicely. Or use it in shampoo's and aftershave, if you want the stimulating effect.
Lavandin: A hybrid between real Lavender and Spike Lavender. This plant grows much faster and bigger than real Lavender. The essential oil is of inferior quality compared to real Lavender (that is, it doesn't have the same medicinal properties). If you want to buy lavender-oil, buy the "real" one and not the lavandin - real Lavender oil is not that expensive, so there is no reason to be economical in this case.
It is possible to buy lavender-oil from plants grown at different heights. The oil from the alpine lavenders contain more esters.
If you want Lavender in your garden, there is A LOT of varieties to choose from. Some cultivars are better suited to your local climate than others. Remember, the real Lavender comes from the mountains of Southern France.
Some uses:
For burns: after having bathed the burn in cold water for a LONG time, drip 1-2 drops of lavender oil (can also be mixed with aloe vera-gel) on the wound. Repeat every 2 hours until it feels better.
Insect bites: rub a little lavender oil on the bite. It disinfects and lessens the pain/itching.
Eczema: Mix lavender oil in your eczema-cream, 5-10 drops pr. 50 ml cream.
Insomnia: a few drops of lavender oil on your pillow, or hang a bunch of lavenders over your bed.
Acne: tame your teenager with lavender! Put a few drops in the cleansing milk/ skintonic, and he/she will get a nicer skin, smell good and get more self-confidence. And maybe calm down a little!!
Candida albicans: try a douche with lavender and tea tree oil.