Vodka and gin

These two belong together because they start the same: a high-strength neutral spirit off a column still, usually from grain, sometimes from potato or beet. What happens next is the difference.

Vodka is distilled to 90–96% and filtered specifically to strip flavour out. It's not aged and tastes of nothing. That's an engineering achievement, and it also leaves little to say about the bottle.

What's left after the flavour has gone is texture. A good vodka is soft and slightly viscous; a cheap one is thin and burns. Base material still shows a little - wheat reads clean and slightly sweet, rye is peppery, potato is oilier and rounder - but at cocktail dilution you're mostly buying mouthfeel.

Gin is that same neutral spirit, redistilled with botanicals. The law puts a floor under the base where vodka has none: it has to come off the still at 96% or higher, so whatever it was made from is gone by the time the botanicals go in. Juniper has to lead - that's the legal definition, and the only thing every gin has in common. Around it sit coriander, angelica root, citrus peel, orris root, cardamom, liquorice, and whatever else the distiller chooses.

It's not aged. Once distillation and flavouring are done the gin is finished, which is why a distillery can be making sellable gin within a week of opening and why so many small producers start there.

There are two ways, and they make different gins. Maceration steeps the botanicals in the spirit and then redistils the lot; it pulls out the heavier, more resinous flavours and gives the classic juniper-forward weight. Vapour infusion hangs them in a basket high in the still so only the rising vapour passes through them, which takes the lighter aromatics and leaves the heavy ones behind. That is most of why a floral contemporary gin tastes the way it does.

Either way the spirit comes off around 75% and is diluted to bottling strength with water. Nothing else may be added to a London Dry after that point.

• London Dry - the dry, juniper-forward benchmark. A method rather than a place: nothing may be added after distillation but water. This is what a recipe means when it just says "gin".
• Plymouth - softer, earthier, slightly sweeter. A protected name from one distillery.
• Old Tom - lightly sweetened, the historical style. What a Tom Collins was originally built on.
• New Western / contemporary - juniper present but pulled back in favour of citrus or floral botanicals. Fine in its own right, and it'll change a Martini.

New Zealand gin has had a decade, and what makes it a category rather than a label is the native bush. Three botanicals turn up again and again, and they do different jobs.

• Horopito, the pepper tree - heat and a green, resinous bite. What grains of paradise do in a London Dry, but hotter and more obviously from a forest.
• Kawakawa - peppery and faintly numbing, related to kava. The one that most changes a G&T.
• Mānuka, usually the leaf - tea-like and soft. Where a gin tastes of the beach rather than the bush, this is often why.

I have poured Scapegrace, The Source from Cardrona, Waiheke Distilling Co, Dancing Sands and Sea Lovers, among others. Scapegrace - the Black especially - and Dancing Sands are the two I would put in a G&T over an imported gin without thinking about it; the Dancing Sands wasabi gin is the one I would hand someone who thinks they know what gin tastes like; and Sea Lovers is a favourite, because it tastes like the ocean in a good way. Others worth knowing by what they put in the still:

• Reid + Reid, Martinborough - all three natives, and the most kawakawa-forward of the lot.
• Little Biddy, West Coast - horopito with rimu and Douglas fir behind it. Spiced citrus and warm resin.
• Dancing Sands, Golden Bay - horopito and kelp in the dry gin, and the wasabi gin off local wasabi root.
• Sea Lovers, Auckland - the marine one: kelp and Waiheke oyster shell over rosemary and lime. Savoury and faintly salty.
• Lighthouse, Martinborough - nine botanicals built on Yen Ben lemon rather than bush. New Zealand grown, not New Zealand bush.
• Broken Heart, Queenstown - eleven botanicals and Mt Aspiring water. More classic than native.

A kawakawa-led gin should sit well in a Negroni - the pepper reads as spice under the Campari rather than fighting it, and the vermouth rounds off the numbing edge. Reid + Reid is the one to try it with.