Three short weeks and then go away...

To begin this beautiful story, we are going to focus on a major work, which attracts each year more than 100,000 visitors from all over the world. And no, it is not the Motor Show. We are even at the antipodes...

Every year in spring, the Royal Greenhouses of Laeken (because that's what they are) open their doors to the public, but only for three short weeks. The opportunity to visit the famous Congo greenhouse, "l'Embarcadère", or to stroll through the long glass gallery in bloom. All this, in the heart of Brussels, but forgetting that we are in the capital, so much we travel through the perfumes, the harmonies of colors and the exceptional architecture that is an integral part of the visit.

A little jump in history is never useless, especially when talking about heritage. It is necessary to put ourselves in the context of the 19th century, during which the progress of building techniques and the use of metal and glass as building materials made a new type of building possible: the greenhouse.

In 1873, the architect Alphonse Balat (who was Victor Horta's teacher) designed, on the initiative of King Leopold II, a complex of greenhouses in the park of the Castle of Laeken, built in classical style. The complex has the appearance of a glass city. But these greenhouses had a totally unexpected effect: they inspired the new Belgian architecture of that time. And their influence will spread, as we know, with the Art Nouveau, throughout the world.

Every year, this jewel is open to the public. A century-old tradition. And last year, the Palace even innovated: visitors to the greenhouses also had the opportunity to stroll through... the Royal Estate.

If these greenhouses are sumptuous, it is also because the current plant collection has a triple exceptional value. First of all, it must be said that it still contains some plants belonging to the original plantations of King Leopold II. Secondly, the plantations of today still correspond, as a whole, to the spirit that presided over the original plantations. Finally, the Royal Greenhouses contain a lot of very rare plants of great value.

Thanks to the monumental pavilions, the glass domes, the wide galleries that run through the grounds... you'll be amazed during the 90-minute visit. One of the highlights of this time is certainly the Winter Garden: topped by a glass crown nearly 25 meters high and 57 m in diameter, its steel frame includes no less than 36 arches resting on a Doric-style colonnade. Built in 1876, it is almost 150 years old and is about to be renovated in a pharaonic project.

Next to this garden, you can also discover the "Embarcadère". Built in 1886-1887, this greenhouse was designed to accommodate guests when the King was entertaining in the Winter Garden or in the Dining Room Greenhouse. And, amusingly, medinillas (a tropical plant from the Philippines) are displayed in Chinese vases brought back by King Leopold II himself, during a trip to the Far East.

But perhaps the most spectacular thing here is what you don't see: the heating! Yes, such greenhouses obviously require extremely precise temperatures. And one can easily imagine how this can strain a budget. Especially in these times... The manager of the place confides: "Before, it was 450,000 liters of fuel oil exactly, while today, we have become almost autonomous and self-sufficient. How did the site managers achieve this feat? By connecting the greenhouse network to... the Neder-over-Heembeek incinerator, via 4.5 km of underground pipes that allowed them to export enough waste heat from the machine to heat buildings and greenhouses. And last but not least, the CO2 emissions of the Royal Estate have been reduced by about 2,300 tons per year. Almost 90% of its heating needs are covered.

See you next spring, in the most beautiful greenhouses of Europe, in the heart of the capital ... of Europe!

In the meantime, if you want to know more about this iconic building turned virtuous, wait for the release of the next LOBBY magazine (soon available via this link), on Tuesday, December 13.

And this weekend, take a leaf out of the greenhouses of Laeken and their managers' book: think about your immediate energy future. It's good for your wallet... and for the planet!