Last updated: November 18, 2021

What Does Hygrometer Mean?

A hygrometer is a device used to measure moisture content and relative humidity in the atmosphere. As humidity is a derived quantity, the measurements rely on other fundamental quantities, like temperature, mass, and electrical charge. Hygrometers play a big part in saunas, greenhouses, industries, incubators, and, most importantly, indoor plant care.

Plants growing indoors are more prone to face humidity problems caused by the artificial environmental conditions and artificial sources of heat and light in the room. Drastic humidity problems in a growroom can cause plants to either dry up or rot.


Maximum Yield Explains Hygrometer

Though it all depends on the garden and the environment around it, a hygrometer can be used to keep humidity problems in check.

While the first hygrometers, invented by Leonardo da Vinci in 1480, were crude and inaccurate, the devices of today are fairly precise. Although humidity is among the most difficult measurements in basic meteorology, after calibration, modern hygrometers are accurate for up to ±3% relative humidity. To calibrate a hygrometer, one has to leave it with a few drops of a salt water mixture for six hours. A few advanced models can also measure moisture content precise up to ±1.2%.

A hygrometer measures relative humidity on the basis of three major factors: mass, temperature, and mechanical and electrical change in the plants. Plants with low humidity levels usually have dried up flowers and leaves, brown tips, and yellow edges. Most of them shrivel and dry up quickly, so to prevent them from dying out, a hygrometer can be used to pre-determine the moisture content of the room, and thus, the health and lifespan of a typical plant.

However, plants with a higher moisture content are also not healthy. High humidity causes the plants to rot, as water acts as a strong catalyst for bacterial growth. Furthermore, the higher levels of water support the growth of fungi, and many plants with higher relative humidity have gray mold on top of their leaves and flowers as a result of breeding fungi.

There are a few plants that need irregular humidity volumes, with some requiring moisture levels significantly higher or lower than the typical houseplant. Many of the exotic plants people like to keep in their gardens are actually native to remarkably different environmental conditions than what is typically found inside a home. Some species like cacti, native to the desert, can survive with surprisingly low humidity levels, while others, like the common orchid, are native to the tropical rainforest and require extremely high moisture levels.

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Tools and EquipmentMetering & MonitoringEnvironmental ControlHumidity

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