Brewers have stepped in to celebrate the man who becomes king on Tuesday after a reputedly boozy time as a student at Leiden university that earned him the nickname "Prince Pils,' after the Pilsner type of lager.

Limited edition beers honouring the future monarch and his abdicating mother, Queen Beatrix, have sprung up around the country.

The "Abdication Beer", produced in the eastern village of Rha, has proved so successful that British brewer Steve Gammage upped his initial production of 1 000 litres to 10 000 litres.

"I used different types of malted barley that give the beer an orange hue," he told AFP proudly.

And what better to drink the beer in than a long glass bearing the text "Prince Pils becomes King Beer, an excellent reason to toast"?

Crockery, figurines and T-shirts, all bearing portraits of the king and his future queen Maxima, are for sale alongside commemorative orange ties and table cloths bordered with orange crowns.

Cakes with orange icing are on offer in almost all bakers, as are orange-coloured chocolate high heel shoes or Willem-Alexander-shaped chocolate bars.

"It's like Cinderella's slipper, only orange, it's a princess's slipper," said a saleswoman who declined to give her name, referring to the chocolate shoe.

Almost all shops here have also taken an approach to their marketing and decorations themed on the national and royal colour, from wrapping paper to window dressing and rosettes pinned to shop assistants.

One company is offering leopard-skin lingerie stamped with an orange crown pattern, while an orange mini vibrator with "Ik Willem" printed on the side is selling fast on the Internet.

The Dutch pun translates into English as either "I, William" or "I want it".

But the trading nation does not want to be burdened with unsellable stock once Tuesday has passed, so retailers also fall back on mainstays that can be sold for sporting events further down the line.

Orange wigs, furry clogs, hair-dye, giant sunglasses can all be had.

"We expect people to spend several million euros on items linked to the enthronement," said Suzanne van de Graaf, spokeswoman for the Dutch Retail Federation.

"An event like this is something people feel positive about, and that means consumers spend more money," she told AFP.

Royal-themed products have come from the most unexpected places.

A manhole cover manufacturer has paid homage to Willem-Alexander, a water management expert, with a commemorative drain cover featuring the royal couple's silhouette.

The company, Aquafix Milieu, has given such a manhole to each of the Netherlands 408 districts, and one has already been laid on Amsterdam's main Dam square.

And with its famously lax policy on soft drugs, even coffee shops are getting in on the act.

In northern city Groningen, the owner of the "Flying Dutchman" coffee shop will on Tuesday hand out baggies of cannabis seeds, which when mature will grow orange flowers.