For growers
Bizon works out VPD from leaf temperature, stores every reading, and sends an alert when a reading leaves the range you set.
Most monitors calculate VPD from air temperature. Transpiration depends on leaf temperature, and the leaf is rarely the same temperature as the air. A well-transpiring canopy with good airflow runs a few degrees cooler; under intense light or weak airflow the radiant load pushes the leaf warmer.
How much that matters depends on the size of the gap. In a well-mixed room under moderate light the leaf is often within a degree or two of air, so the correction is small. But a 4 to 5°F difference, common under strong light or right when the light drops off, moves the leaf VPD by roughly 0.3 to 0.7 kPa between 68 and 85°F, enough to put you in a different zone than the air number claims. The leaf-to-air gap also shows how much the light is heating the canopy and whether transpiration is keeping up.
When the leaf goes from cooler than the air to warmer, the light is heating it faster than transpiration can cool it.
Illustration only.
Readings from every room, garden or greenhouse you add, in the same account as the growing tools.
An infrared sensor reads leaf temperature, and VPD is calculated from it.
Temperature, humidity, VPD, CO2, and canopy across rooms, with charts of past readings.
Email and push notifications within one reading (5 minutes by default) of a reading drifting past the range you set.
Add Bizon to your phone's home screen and get alerts even when the browser is closed.
See how far your canopy runs from air, and how the light loads the plant day versus night.
Feeding, soil and water analysis, lighting, IPM protocols, and logs, in the same account.
Your data is yours. Readings export as CSV, and the account can be deleted anytime. See our Privacy Policy and Terms.