Humidity Management in Greenhouse 

The excess level of humidity in the greenhouse is a great problem. Diseases can spread from the condensate dripping from the ceiling. The formation of water poodles on the floor of the greenhouse unit encourages the growth of algae and insect breeding. It is also responsible for creating hazardous working conditions for the workers in the greenhouse.

The transpiration of plants is disturbed due to the high level of humidity in the air. The condensate droplets on the ceiling and walls formed due to high humidity also reflect light. The transmission of light is greatly reduced due to this which can affect plant growth. Read more on Dehumidifiers for Greenhouses in New Zealand. 

Too little humidity is also stressful for plants. It results in the acceleration of transpiration in plants. Transpiration in plants more than their roots can take up and translocate can be fatal for the plants in the greenhouse. The only solution to these humidity problems is the installation of systematic humidity management. Read more on Dehumidifiers for Grow Tents in NZ. 

What is Humidity? 

At a certain temperature, air can hold a certain amount of moisture in them. The relative humidity is the ratio of the amount of moisture in the air at a certain temperature to the amount of moisture the air can hold at that moisture. Air can hold more water at higher temperatures hence temperature has a big impact on relative humidity. One of the examples of the effect of temperature in relative humidity is air at 80 percent humidity level at 68 degrees Fahrenheit have only 56 percent relative humidity at 79 degrees Fahrenheit. Read about Drying Compressed Air to Protect Plants in NZ. 

The temperature at which the humidity level of the air reaches 100 percent is known as the dew point. Condensation occurs when air at the dew point comes in contact with a cold surface. Read about Dehumidification in Medical Cannabis Greenhouses. 

Another important term in humidity management is the vapor pressure deficit. It can be defined as the difference between the moisture in the air and the amount of water vapor the air can hold in saturation. Another way of defining vapor pressure is it is the difference between the amount of moisture in the air and how much moisture can be found on the leaf surface. Read more on How to effectively control humidity levels in Greenhouses? 

A vapor pressure difference is the driving factor of transpiration. Translocation, nutrient uptake, and photosynthesis all are affected by transpiration. The increase in vapor pressure causes drought stress in plants as the translocation of water from the roots to the leaves is lower than the transpiration.

The measuring unit of vapor pressure deficit is kilopascals. One kilopascal equals 1000 newton of force in a unit square meter of surface. One thousand newtons is equal to 225 pounds of force. VPD is calculated with the help of temperature and relative humidity. The ideal Vapor pressure deficit for a greenhouse is in the range of 0.45 kPa to 1.25 kPa.

If the vapor pressure deficit is higher in the greenhouse then the dryness of the air also increases, while the decrease in Vapor pressure deficit increases moisture. When the vapor pressure deficit is high the crops are unable to keep up with the transpiration demand and the lower vapor pressure deficit increases the growth of fungus and raises other disease concerns.

As a professional one must understand that each and every crop has a different requirement of vapor pressure deficit. The optimal vapor pressure in a crop can also change according to the growth stage of the crop. Read more on Dehumidification in honey Extraction Facilities in NZ. 

Managing Humidity 

You have to begin with ‘grow dry’ tactics as the starting point of humidity management. This is the most energy-efficient method in humidity management. “Grow dry” focuses on providing the plants with just enough water to meet their needs. It is almost like controlled irrigation. Minimizing water waste is the main focus of this system. Watering the plant at the right time is one of the important parts of this tactic. Avoiding watering the plants before sunset is important according to the experts. The water overnight can cause few problems. It can cause an increase in humidity in the morning and disturb the transpiration and photosynthesis in plants.  Other elements of “growing dry” are eliminating condensate collection points, draining condensate, and considering condensing.

The reflection of light off droplets from condensate can be avoided by draining condensate. Circulating air throughout the greenhouse unit helps to keep the humidity evenly distributed. There are new technologies popping up which helps in warming plants with heat piping which helps to ensure a dry greenhouse. The goal is to minimize the stay of water on plants as long stay of water on leaves causes promotes fungal growth.

But only these methods may not be enough to bring the humidity in control. Dehumidifiers by Ambale Co. is the most professional method to manage dehumidifiers. Our expertise lies in the HVAC system of greenhouse units. Our services can be accessed all over New Zealand that includes cities like Auckland, Hamilton, Napier, Tauranga, Christchurch, wellington, etc. Our dehumidifiers are considered the best dehumidifiers in New Zealand. 

Contact us at or dial +64 22 061 7007.

We also provide humidifiers, air purifiers, data-loggers, sensors, etc.