The big, heavy-crowned palm you see on every promenade from Tenerife to Torquay is a Canary Island native — Phoenix canariensis, the Canary date palm — and it is the official natural symbol of the archipelago. It is also one of the most successfully exported plants in history: the seafronts of Nice, Los Angeles, Sydney and half the Mediterranean are planted with a tree that evolved on these islands and nowhere else.

Up close it is unmistakable once you know what to look for. A single massive trunk, never a cluster. A crown so dense it looks upholstered, with anything up to a couple of hundred fronds arching out and down in a near-perfect globe. And, where old leaves have been cut away, a trunk patterned in neat diamonds — the scars of the leaf bases, stacked like a woven basket.

What it does not do particularly well is produce dates. The fruit is small, mostly stone, with a thin orange flesh that is edible in the technical sense and disappointing in every other. If you want a date, you want the other species. If you want a tree that shrugs off wind, salt, drought and neglect while looking magnificent, you want this one — which is precisely why the world planted it.

Telling it from the true date palm

Its close relative Phoenix dactylifera, the true date palm of North Africa and the Middle East, grows all over the islands too, and the two are constantly confused. Four reliable tells:

The confusion matters more than it sounds. The two species hybridise freely, and imported date palms planted near native groves have been steadily contaminating the wild gene pool. Islands with important groves now restrict what can be planted nearby, and nurseries certify seed origin. A hybrid looks broadly right and is, botanically, the beginning of the end of a species.

How it became a symbol

In 1991 the Canarian parliament passed a law assigning natural symbols to the archipelago and to each island. The Canary date palm and the wild canary — the small streaky green finch, not the yellow cage bird — were chosen to represent the islands as a whole, with the dragon tree and others assigned island by island. The palm won because it grows on all seven islands, because it is genuinely endemic, and because it had underwritten village life for centuries in a way no other plant quite did.

What a palm was actually for

Not shade, and not scenery. On a poor island a palm was a hardware shop. The fronds were split for basketry, woven into hats, mats, ropes, brooms, fish traps and panniers for donkeys; the leaf midribs made frames and fencing; the fibre at the crown was used for stuffing and cordage; the fruit fed pigs and goats even where it did not feed people; and the palm heart, taken when a tree had to come down, was eaten. Much of that survives as craft rather than necessity, and palm-leaf work is still one of the better things to bring home among the islands' traditional crafts.

The fronds have one more job. Before Palm Sunday, whole crowns are bound up so the emerging leaves grow blanched and pale, and those cream-coloured fronds are carried in procession during Holy Week. A tree bound for Palm Sunday is a common enough sight in the countryside in late winter.

Palm honey, and the man with the knife

The most extraordinary use is on La Gomera, where the palm is tapped for its sap. It is a genuinely difficult craft. A palmero climbs the tree — with a rope loop and no scaffolding, in the traditional method — cuts away the crown to expose the growing point, and shapes a sloped surface from which sap will run. That sap, guarapo, is collected into a vessel every evening and morning, because in the heat of the day it ferments within hours.

A good tree gives several litres a night, and it is then boiled down hard — something in the order of seven parts sap to one part syrup — into miel de palma, a dark, smoky, faintly bitter treacle that tastes nothing like honey and is poured over fresh cheese, over almond desserts, into rum and, by Gomerans, onto more or less anything. Our page on palm honey and how to use it goes into the taste and the buying.

Here is the detail that explains why the stuff costs what it does. A tapped palm stops producing fruit and stops growing new crown while it is in production, and it takes years to recover afterwards — some are tapped for a season and rested, some are effectively worked out. The number of trained palmeros on La Gomera has fallen to a few dozen, all of them ageing, and the craft is formally recognised as heritage precisely because it is close to disappearing. You are not buying a condiment, you are buying the last few years of a very specific skill.

The great groves

Wild and semi-wild palm groves — palmerales — fill ravine bottoms where there is enough subsurface water, and they are among the most beautiful places in the archipelago.

On Gran Canaria the classic is the valley above Maspalomas, where Fataga sits in what the tourist board calls the Valley of a Thousand Palms, and the extensive groves around Santa Lucía de Tirajana in the southern uplands. At the coast, the small freshwater lagoon behind the Maspalomas dunes is fringed with palms and reads as an oasis for the perfectly good reason that it functions as one.

La Gomera has the densest concentration in the archipelago, on the terraced slopes above Valle Gran Rey and in the southern valleys around Alajeró. La Palma and the Anaga valleys on Tenerife have their own. And for the botanically minded, the Palmetum in Santa Cruz — a palm collection built on a reclaimed rubbish tip, which is a story in itself — puts canariensis beside a few hundred of its relatives so you can see the differences at a glance. The Jardín Botánico Canario outside Las Palmas has a fine grove too.

The weevil

The gravest current threat is an insect. The red palm weevil, a large reddish beetle originally from tropical Asia, spread through the Mediterranean with the trade in ornamental palms and reached Spain in the 1990s. The grubs eat the growing point from the inside, and by the time a crown starts to droop the tree is usually already dead. The Canaries have fought outbreaks with quarantine, trapping, treatment and the destruction of infected trees, at considerable cost.

It is a good argument for not moving palms about, and it is why you may see a fine old palm suddenly felled and chipped: a dead palm left standing is a weevil factory for the whole valley.

How to look at one

Get underneath a big one and look up through the crown — the geometry of a few hundred fronds radiating from a single point is the best thing about the tree. Look for the diamond-scarred trunk. Look for the golden-orange flower spikes that hang out of the crown in spring, and the huge dangling bunches of fruit in autumn. And notice how often a village palm stands beside a water tank, a threshing floor or the remains of a farm: palms follow water and people, and a lone palm on a hillside almost always marks where somebody once lived.

The bottom line

The Canary date palm is the islands' most visible export and their most useful native plant, and it repays the two minutes it takes to learn to identify it properly. Spot the single trunk and the dense round crown once and you will be doing it on holiday for the rest of your life, in places thousands of kilometres from here.

If you take one thing home, make it a jar of palm honey from La Gomera. And if you want to see the tree in the landscape it evolved for rather than on a promenade, drive up into the ravines of southern Gran Canaria in the late afternoon — the light through a palm grove is the reason Canarian plant life gets people permanently hooked.