The Miraculous Ecosystem Encountered in a 100% Humidity Plant Factory

Hello everyone! I’m Shohei.
This column is written mainly based on my field experience.
After being on site for over 10 years, there are truly many things that happen. I’m writing about things I remember, as they come to mind.
Well, please read it casually, like “Oh, so that’s how other factories are.”

“Underwater Agriculture!?”

“Thank you for having me today.”
On the day I visited a client’s plant factory, I politely bowed while adjusting my suit collar. As a consultant called in for facility improvement, what my eyes encountered was a scene beyond imagination.

Tropical Rainforest? Sauna? No, It’s a Plant Factory

The moment I opened the door to the cultivation room, I was hit with a sensation like running into a wall.
“It’s so… humid…!!!”
It felt like my lungs were filling with water just by breathing. My glasses instantly fogged up completely, reducing visibility to zero.
And from beneath my feet came an ominous sound.
Splash, splash, splash.
After wiping my glasses, I saw that the floor was submerged under about 1 centimeter of water. It was like small streams were flowing between the growing beds.
“Umm… this water…?”
“Oh, this? It’s just condensation collecting from the walls.”
The factory manager answered in a casual tone as if saying, “Would you like some coffee?”

“Is This… a Fish Farm?”

Looking at the humidity meter, the display showed “99%.” This should normally be the limit, but I could feel humidity clearly exceeding that. It was beyond mere humidity—it felt like standing in fog.
Looking at the walls, water was flowing down like waterfalls. Droplets were also falling from the ceiling.
“What about dehumidifiers…?”
“We don’t have any.”
At that answer, I was mentally screaming, “Isn’t that a major problem?!”

“The Identity of That Strange Organism Is…”

While examining the cultivation shelves, I discovered a peculiar plant.
“Is this… a new experimental variety?”
A single, slender stem extended from the urethane foam, with a few small leaves at the tip. It resembled carrot leaves in appearance, but was clearly different. It looked almost like aquatic vegetation desperately trying to surface from underwater.
The factory manager answered somewhat sheepishly:
“No, this is lettuce.”
“…What?”
“Frilled lettuce.”
I couldn’t believe my eyes. When you think of lettuce, you imagine leaves spreading out in a fluffy manner, but the “something” before me didn’t look like anything that could be commercialized. It was like a zombie from the plant kingdom.
At that moment, the term “etiolation” from plant physiology classes flashed in my mind. It’s a condition where high humidity and weak light cause abnormal elongation of internodes, resulting in an appearance far from its normal state.

“Emergency Rescue Operation”

The situation was clear. This plant factory had turned into an “aquarium.”
There were no dehumidifiers in the facility, but fortunately, multiple air conditioners were installed. As an emergency measure, I proposed the drastic technique of running both cooling and heating simultaneously.
“Simultaneously? Wouldn’t that cost a fortune in electricity…?”
“This is no time to worry about that! This is a plant rescue operation!”
And several hours later, a miracle occurred. The humidity meter readings began to drop gradually. 95%… 90%… and by the next day, it improved to the 80% range.

“Afterwards…”

Later, we formally introduced dehumidifiers and improved the drainage system. And when I revisited a month later…
“So this is what real lettuce looks like…”
The former “underwater creatures” had grown into proper lettuce.
I learned from this experience how important “proper humidity management” is in a plant factory.
…Sometimes I remember the sight of those strange “underwater lettuce” plants. It was an unforgettable plant factory experience that taught me both the strength and delicacy of plant life.

This column is sourced from a collection of know-how for improving field operations

This column is published in the following content available for purchase on our site.
It’s packed with know-how that helps improve profitability in the field.

While it’s a bit pricey, we believe it offers good value for money.
It’s essential reading for those involved in plant factories or facility cultivation.