What kind of chilli is that?

Species or type?

Sweet and frying peppers

No real heat. Grown for flesh and flavour.

The bottom of the scale, where a pepper is a vegetable. Thick-walled sweet types like the piquillo and the Florina are grown to be roasted and skinned; the long, thin-walled Italian frying peppers — cubanelle, Jimmy Nardello — are for the pan, where they collapse into something sweet and faintly smoky in a couple of minutes. Nothing here needs seeding or handling with care, and the only reason to grow them over a supermarket bell pepper is that the varieties worth eating are almost never sold fresh in Britain.

Blistering peppers

Eaten whole and young, in hot oil. Roughly one in ten bites back.

A small group with a shared trick: picked deliberately immature, fried whole until the skins blister, salted, and eaten with fingers. Padrón in Galicia and shishito in Japan arrived at the same idea independently, and both carry the same lottery — most are sweet and grassy, and every so often one is properly hot. Timing is everything. Left on the plant an extra week they toughen and heat up, and stop being this kind of pepper at all.

Jalapeño types

Thick walls, picked green, mild to medium. The stuffing peppers.

Blunt, thick-fleshed pods usually picked green and used fresh. The thick walls are the defining feature and they decide everything else: these are the peppers that stuff, slice and pickle well, and that dry badly — which is exactly why jalapeños are smoked into chipotle rather than sun-dried. Heat is modest and, in commercially bred strains, deliberately lower than it used to be. Left to ripen red they sweeten considerably.

New Mexican and Anaheim types

Long, mild, green. Roasted by the sackful.

Long, flattish, thick-walled pods bred at New Mexico State University over more than a century — the longest continuous chile breeding programme in the world — and grown at a scale nothing else here matches. They are picked green, roasted until the skin lifts, and used as a vegetable rather than a seasoning: green chile stew, chiles rellenos, anything with pork. Ripened red and dried they become the ristra, and a completely different sauce. The Anaheim is the same lineage after a century in California, and whether that makes it a separate variety is still argued over.

Poblano types, fresh and dried

Heart-shaped, mild, and the backbone of mole.

Large, dark, heart-shaped pods with thick walls and a deep, almost vegetal flavour that only really appears once they are charred and peeled. Dried, they change name and character: a red-ripening poblano dries to the sweet, raisiny ancho, a brown-ripening one to the darker, smokier mulato, and the related chilaca dries to pasilla. Those three are the trinity most moles are built on, and they are not interchangeable — which is why a recipe worth following names all three separately.

Wax and banana types

Smooth, waxy, yellow, and constantly mislabelled.

Tapering yellow pods with a distinctively smooth, waxy skin that holds up in brine — which is why this group dominates the pickle jar. The catch is that the mild banana pepper and the genuinely hot Hungarian wax look nearly identical and are mixed up routinely on market stalls. The difference is not visual: one tops out around 500 SHU and the other reaches into the thousands, so when it matters, taste before you commit a whole dish.

Cayenne and drying types

Long, thin-walled, and built to be dried.

Slender, tapering, thin-walled pods that give up their water quickly and evenly — the reason this shape dominates the world's dried-chilli trade. Thread them on a string in a warm kitchen and they keep for a year; grind them and you have most of the powders in a spice rack. The group covers an enormous geographic spread under different names, from cayenne itself to the Kashmiri chillies grown for colour rather than heat, and the Mexican guajillo and árbol.

Bird's eye and wild types

Tiny, upright, fierce. The shape chillies started as.

Small pods held upright and clear of the foliage, borne in enormous numbers on compact plants. This is close to the wild form — the chiltepin is the most likely ancestor of nearly every domesticated Capsicum annuum on earth — and the shape exists for a reason: birds cannot taste capsaicin, so they eat these whole and pass the seeds intact, while mammals that would grind them up are warned off. Almost every warm country has its own, under its own name.

Habanero and Scotch bonnet types

Lantern-shaped, fiercely hot, and unexpectedly fruity.

Wrinkled, lantern or bonnet-shaped pods with thin walls and an aroma that is the whole point of them — apricot, citrus, something almost floral arriving alongside heat that starts around a hundred thousand Scoville units. Habanero and Scotch bonnet are the same species and close enough to substitute at a push, though a Jamaican cook would disagree. The aroma is fragile: it is the first thing lost to prolonged cooking, so these go in late or raw.

Superhots

A million Scoville units and up. Mostly bred, not grown traditionally.

The modern end of the scale, and almost entirely a product of the last twenty years of deliberate breeding for records. Wrinkled, blistered, often with a stinger tail, and hot enough that the handling advice stops being decorative. Underneath the heat there is usually genuine chinense flavour, which is why the good ones end up in sauces rather than only in dares. Britain is unexpectedly well represented here.

Ají types

South American, fruity, and frequently citrus.

The chillies of Peru, Bolivia and Argentina, and the group most likely to surprise someone who thinks they know what a chilli tastes like. Flavour is the draw — bright, fruity, often frankly citrusy — with heat that mostly stays moderate. They are easy to spot in flower, because this species carries tan or yellow-green spots on the corolla that none of the others have. Plants grow tall and want a long season, so British growers should sow early.

Rocoto and manzano types

Thick-fleshed, black-seeded, and the one that likes our weather.

The odd group out, and unmistakable once you know the signs: black seeds, purple flowers and hairy leaves. Rocotos come from the Andean highlands and behave accordingly — they tolerate cool, damp conditions that stop other chillies dead, keep fruiting into a British autumn, and can be overwintered as a perennial for years. The flesh is thick and apple-crisp rather than papery, so they stuff beautifully and dry not at all.

Working out what you're holding

Common questions

How many types of chilli are there?

There is no fixed number, because chillies are classified two different ways. Botanically there are five domesticated species. Practically, chillies are grouped by pod type — jalapeño, cayenne, habanero, New Mexican and so on — and there are a few dozen of those depending on who is counting, each covering many named varieties.

What is the difference between a chilli species and a pod type?

Species is botany: it tells you which plants will cross with each other. Pod type is shape, wall thickness and use, and it is what a cook actually cares about. They cut across each other — a poblano and a Carolina Reaper share a genus but nothing else useful, while a habanero and a Scotch bonnet are the same species and nearly interchangeable in a pot.

Which type of chilli should I grow in the UK?

Start with an annuum — jalapeño, a cayenne, Hungarian hot wax or a Padrón. They germinate readily, ripen in a British season and forgive mistakes. Chinense types like habaneros and superhots need sowing in January or February under a propagator and finishing under cover. Rocotos are the dark horse: they actively prefer cool, damp conditions.

Which chilli type is best for drying?

Anything thin-walled — cayenne types above all, then bird's eye and most superhots. Thick-walled peppers like jalapeños and poblanos dry badly and go mouldy before they go crisp, which is why those two are preserved by smoking and by drying as ancho respectively rather than hung on a string.