Five years after first proposing the construction of three glass domes on its downtown Seattle campus, Amazon is set to welcome employees into its fully realized, plant-filled Spheres next week, and herald yet another perk of working for the ever-growing tech giant.

The idea of meeting, working or relaxing among 40,000 plants from more than 30 countries, in an enclosed tropical climate in the middle of Seattle, was conceived as a way to help Amazonians “think differently” — to get away from traditional workspaces and get up close to nature.

Many of those traditional workspaces loom over the Spheres in Amazon’s high-rise Doppler and Day 1 towers which bookend the Spheres at Lenora Street between Sixth and Seventh Avenues in the city’s Denny Triangle neighborhood. The transformation of this part of the city, stretching north throughout South Lake Union, is part of Amazon’s effort to rethink how corporate campuses are built in an urban setting.

The glass biodomes, or orbs, or balls — or whatever else they have been called since taking on their official name — have been an architectural curiosity in Seattle since they began to take shape. Construction crews broke ground on the Spheres in 2015, and completed the steel skeleton a year later.

But, sorry, the most dramatic interior aspects of the Spheres are for use by Amazon employees only.

Beyond three retail experiences at street level where the public will have access, non-employees will have to register for an official Amazon headquarters tour to see more. Even employees must use a reservation system in the early going — it’s already booked through April — to keep the Spheres from being overrun by a crush of people from the company, which has 40,000 employees in Seattle alone.

“There’s an amazing teaching moment here, and we envision being able to open these Spheres to the public occasionally for field trips and for educational purposes with different schools and universities,” said John Schoettler, Amazon’s vice president of global real estate and facilities. “This is our office space, and we don’t invite the public into any of the towers. This is just an alternative working space for our employees.”

In a city where the futuristic Space Needle has long been the talk of the skyline, Amazon and the architectural designers at NBBJ have created a 70,000-square-foot focal point for a new generation of Seattleites — many of them tech workers attracted by the city’s booming economy.

So what does it feel like to go in and veg out? Ahead of next week’s grand opening, GeekWire got a look during a tour with Schoettler and Ron Gagliardo, the senior manager of horticultural services, whose team has been researching, raising and planting the many species that inhabit the new building.

Coming in off a rainy, cool Seattle sidewalk in February, the first thing that hits you is the temperature and the humidity. Outside, the temperature was in the low 40s, but inside it felt kind of muggy. The temperature will be kept near the low- to mid-70s during the day, with a humidity of 60 percent. The climate is meant to mimic that of an altitudinal zone found in Costa Rica or Indonesia — and the first thing I did was remove my jacket.

Schoettler said that the operating mantra is “people first, plants second,” meaning that a lower temperature is meant to offset the higher humidity, and Amazon surely doesn’t want people to be uncomfortable in a space designed to make them feel great.

At night, the humidity will be jacked up to 80 percent, but the temperature comes way down to maintain a consistent feel. The plants will love that, but the employees should be home asleep by then.

The idea is to experience something different than the desk over in Day 1 or Doppler.

The smell also catches you immediately upon entering. The combination of plant life, soil, ground cover and the misty, humid air definitely lets you know that you’ve stepped away from your desk and left whatever it smells like in a typical Amazon office setting. (Coffee? Someone’s reheated lunch? A dog or three?)

The giant, 4-story living wall — a focal point of the Spheres — contributes a good deal to that immediate ground-level sensation, with 25,000 plants woven into the 4,000 square feet it occupies.

“You pass this living wall and you think, ‘This is amazing,'” Gagliardo said. “The idea is to experience something different than the desk over in Day 1 or Doppler and kind of put into practice one of our leadership principles of learn and be curious.”

There are plenty of pathways to take on that curious journey. Stairways head toward the treetops and the upper levels of the 5-story structures. They also descend to the base of a water feature. Walkways wind around the perimeter and weave through clusters of plantings. There is a wooden “bird’s nest” seating area in the sky at the end of suspension bridge of sorts. There are wooden benches and metal tables, chairs of all shapes and meeting spaces large and small. Every turn seems to look, feel and smell different.

We encourage people to get up and wander around and find their favorite spots and explore and find new spots.

“There’s tons of microclimates. You’ll find places that are warmer and some places that are cooler,” Schoettler said. “That’s by design, the way that the air movement is happening in a specific area for the plants that are in that area. People will be able to help modulate and regulate — it’s part of discovery, actually, and we encourage people to get up and wander around and find their favorite spots and explore and find new spots.”

As far as sounds, when GeekWire visited there was still some light construction happening, and noise associated with getting the place in top shape. Gagliardo expects it will quiet down.

“You’ll probably hear the din of people talking and that sort of conversation, but it will be sort of buried in the background,” he said. “You’ll probably hear lots of people going, ‘Wow! Ooh! Aah!'”

From the ground to the top of her canopy, it’s cool to see Rubi, the 55-foot-tall Ficus rubiginosa tree that was trucked from California and hoisted into the Spheres last June. The tree is the largest specimen on site, and with her branches stretching toward the light above, the 48-year-old tree looks like it was born in the building.

That mindset has been part of the project since the beginning, when Amazon CEO Jeff Bezos first looked at pictures of good-sized trees and was told how big they would potentially get in the early years after they were transplanted.

“Can we have year five on day one?” Bezos asked, according to Gagliardo. That’s why things look the way they do — mature.

“We had the luxury of having the time to be able to do this, to make this an impactful horticultural experience,” Gagliardo said.

The preparation that took place in a large greenhouse in Woodinville, Wash., has served the Spheres well. Gagliardo said he can count on one hand the number of plants that have been sent back to the greenhouse because those plants didn’t fully appreciate how good they needed to look for the grand opening.

In the area where the very first plant went into the Spheres last May, there’s a species of rhododendron from the Philippines on display that is extinct in the wild, and Gagliardo and his team believe it’s another example of the educational process that can happen in the space, how it can get people excited about conservation.

This was an opportunity to raise the bar. I believe we’ve set a really high bar.

And while he may know seemingly all there is to know about plant life, Gagliardo, who has been with Amazon for just over four years, does not fancy himself a landscape designer. That credit goes to Seattle based landscape architecture firm Site Workshop, who collaborated with NBBJ. Schoettler further praised the team at NBBJ and the research and worldwide travel that was done to better understand which conservatories were doing things right.

“This was an opportunity to raise the bar,” Schoettler said. “I believe we’ve set a really high bar,” he added, calling the living wall a work of art, and one of the most beautiful examples of that type of feature in the world.

Elsewhere, there are paludariums scattered around the spheres. The modified aquariums feature both terrestrial and aquatic plants and specimens. One represents the flooded floor of the Amazon rainforest, and another uses an ultrasonic fogger to create a smoky mist that is beneficial to the Bornean plants within. There are even fish to gawk at through the glass.

Terrariums hung on the walls in lower light settings also put much smaller plants right in front of people’s faces — but prevent those people from touching. And that’s a rule that applies throughout.

“We have asked folks to refrain from touching,” Gagliardo said. “We’ll have some horticultural ambassadors wandering the building, and they’ll be armed with props. So they’ll have things in their hand and they’ll go to people and say, ‘Hey, touch this, rub this, smell this.'”

And there won’t be any dog petting or sniffing or anything else that already happens in the planted areas outside the Spheres. Only service dogs will be allowed inside, not the normal gaggle of office pooches seen around campus.

But the thousands of Amazon employees won’t be entirely alone with the plants. Insects are being released inside the Spheres to combat any bad bugs that can flourish inside a conservatory-type environment, such as aphids. This process is necessary because the company can’t spray pesticides around that many people.

While there are splashes of color from blooming plants here and there, most of what’s on display looks lush and green, with varieties of palms and ferns for example. There’s not an area that you can go and walk through like a rose garden, for example, to get a more exaggerated display of color and smell from blooming flowers.

But there will always be something in bloom or something that you can smell if you get close enough.

“If you’re here at 6 o’clock, you would smell a skunk over on that side of the conservatory,” Gagliardo said, alluding to a plant that puts off an odor during the later hours of the day.

Perched atop one waterfall is a sizable tree fern that outgrew its home in the conservatory at Seattle’s Volunteer Park. “You can have it if you come get it,” the staff there told Amazon.

The process has been all about assembling a unique collection of many varied species.

“This isn’t a shopping mall where we just replace plants every month,” Gagliardo said, standing beneath a cocoa tree. “We wanted a place that was comfortable for people and able to sustain a more permanent plant collection. I think in order to sustain people’s interest, we have to show them plants they can relate to.”

Amazonians will also be able to relate to the food and drink available inside the building. Seattle chef and restauranteur Renee Erickson is providing food services in the Spheres with another of her General Porpoise doughnut and coffee locations, and a ground-floor counter that provides lunch items.

There is a restaurant and bar planned, also under Erickson’s name, that will be open to the public. And Understory, on Seventh Avenue, will further convey the story to the public by using photographs and videos to describe how the Spheres came to be and what’s happening inside now.

So what do the Spheres ultimately say to the Amazonians who they were designed for? And what do they say to the people who don’t work for the tech giant?

“This is why you work for us”? or “Here’s another reason why you should work for us”?

“I think it says both,” Schoettler said. “As you know, we invested an awful lot in our urban campus. And we could have gone to the suburbs and we could have taken some farmland and knocked down some trees and we would have been more out in natural surroundings.

“We decided to bring nature into the city and create this amazing space.”