Inside an automated plant lab in orbit

The station's largest plant growth chamber is a closed, automated chamber that fills part of a standard equipment rack. LEDs in red, blue, green and white provide light, a clay based root module delivers water and nutrients, and more than 180 sensors plus cameras let scientists on the ground watch and adjust the crop. Its environmental control system holds temperature, humidity and air flow steady, which together set how fast leaves lose water.

Controls

Labels

Animation speed

LED output

Chamber temperature

Relative humidity

Step through it

A plant lab in a rackThe chamber fits into a standard station equipment rack. It can run a crop experiment for up to about 135 days with little crew time.
Tunable LEDsRed, blue, green and broad white LEDs can be mixed and dimmed. Scientists use the light recipe as an experimental variable.
Roots in clayRoots grow in a porous clay substrate with slow release fertilizer. Water is fed in and held by capillary forces, since it cannot drain downward in orbit.
Watched by sensorsMore than 180 sensors track temperature, oxygen and moisture in the air, root zone and plant tissue, and cameras send images to the ground.
Air that is too dampRaise the humidity to 90 percent and the vapor pressure deficit falls very low. Leaves can barely transpire, which slows the flow of water and nutrients.

Vapor pressure deficit

VPD is the gap between how much water vapor the air could hold at its temperature and how much it holds now. Saturation vapor pressure follows the Tetens formula: es = 0.6108 x e^(17.27 x T / (T + 237.3)) kPa, with T in degrees Celsius. Then VPD = es x (1 minus RH / 100).

Many growers aim for a VPD of roughly 0.4 to 1.2 kPa for leafy crops. In microgravity there is no rising warm air, so fans are essential to keep humid air from sitting on the leaves.

Try it: hold humidity at 70 percent and move temperature from 18 to 30 °C. The VPD more than doubles, from about 0.6 to 1.3 kPa, because warm air can hold much more water.

Light and power (simplified)

This model assumes the LEDs reach 1,000 micromoles per square meter per second at full output, over about 0.2 m² of growing area, at an efficacy of 2.5 micromoles per joule. These are teaching assumptions, not the chamber's published specifications.

Where Avid uses this

VerdantaIQ, Avid's precision agriculture AI, also turns sensor readings into crop decisions, in its case for irrigation in the field.

Sources

Growth Chambers on the International Space Station for Large PlantsNASA Technical Reports Server
Dewpoint and Vapor Pressure Deficit EquationsOregon State University, H.J. Andrews Experimental Forest
Advanced Plant HabitatNASA Science

How to cite this model

Avid Solutions International. (2026, November 11). Inside an automated plant lab in orbit [Interactive 3D model]. Avid Field Lab. https://avidsolutionsintl.com/explore/advanced-plant-habitat

Last updated November 11, 2026

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