By no means is this an exhaustive list! I'll keep adding to it!
One of the most prevalent botanicals in gin, the root is most commonly used, but the seeds are sometimes used too. Producers cite it's properties as a binding agent, as well as it's earthy flavour. Angelica is also found in Chartreuse.
Coriander seeds are found in almost all gins, and are sometimes roasted or crushed to alter the flavour profile. Coriander seeds are responsible for providing the 'high citrus' notes towards the end of the taste.
Flowering in late May to Early June, elderflowers can be found in abundance in the British countryside. Warner Edwards steeps it's Harrington Dry Gin at 89% abv, for a week with Elderflower petals, adding sugar & water to create their Elderflower Gin, bottled at 40% abv.
A resin tapped from the bark of the Boswellia Sacra tree, found in Arabia and North Africa, and used as an incense. Sacred Gin takes it's name from the use of Frankincense where it provides a gentle warmth.
G: Green Cardamom
I: Iris Root
Or Orris Root, is also used in perfumery, where it is dried for around 5 years before use. Orris root is used as a base note to bind other flavours, with an underlying woody, oily properties.
What makes Gin, Gin! Juniper berries are sweet, along with pine notes and grows across huge swathes of the world - in Britain it's particularly common in the Scottish Highlands. Legally gin must be predominantly flavoured with Juniper.
K: Kaffir Lime Leaves
A traditional sweetener in gin historically, liquorice root was prevalent when sugar was prohibitively expensive during the gin craw of the 1700s.
Native to South Asia, this citrus fruit resembles a large grapefruit, but the taste is a sweeter citrus, without the bitterness. Monkey 47 uses it as part of it's mix of 47 botanicals.
S: Silver Birch
U: Urtica Dioica - Stinging Nettles
Native to mexico, Vanilla pods come from a flowering vine, with takes 3 - 5 years to bloom - now Indonesia and Madagascar are the biggest producers. Sloanes Gin uses this to deliver a smooth creamy gin.
Extremely bitter, wormwood is more famous for being used in Absinthe, but you'll also ind it in bitters, vermouth and in the rather delicious Bath Gin. 'Artemisia Absinthium' is toxic if consumed in large quantities, but is often used to relieve indigestion.
X: Nope. I've Got Nothing.
Ok so this is a bit of a cheat for Z, but almost all gin uses citrus zest in some form to balance the sweetness of Juniper. Dried or fresh, with the more common lemon through to grapefruit as exhibited in Tanqueray 10.