Effective Greenhouse Humidity Control

One of the great challenges in a greenhouse is to maintain the humidity level to the desired level for the optimum growth of the plants. Ambale Co. has been providing effective greenhouse humidity control to the large greenhouse firms in New Zealand for a long time. We provide specialized services to our clients all over New Zealand. Our services are available in cities like Wellington, Napier, Hamilton, Auckland, Dunedin, Christchurch, Tauranga, and many more. Read about Dehumidifiers for Greenhouses in detail. 

Promoting a healthy and dry environmental condition is said to be the best defense against fungal infection in crops in a greenhouse. It is very important to control the temperature and humidity to avoid the accumulation of water on the tissue. Read our article on Humidity Management in Greenhouse. 

The most dangerous hours for the plants in the greenhouse are the time after the sunset. The temperature suddenly drops down after the sunset in comparison to the daytime. The cooler night causes the glazing to become cold and the plants radiate to the cooler glazing. After a certain point, the glazing or the foliage reaches the dew point causing wetness in the greenhouse unit.

One of the ways to reduce plant radiation cooling is to use overhead curtains or screens. It has been found that the use of overhead curtains significantly reduces the rate of plant radiation cooling. Ventilation, condensation, and desiccant dehumidification are other methods of effectively controlling the humidity in a greenhouse unit. Read more on Dehumidifiers for Medical Cannabis Greenhouse in New Zealand. 


The most traditional method of controlling humidity is ventilation. One of the drawbacks of ventilation is it does not provide proper control to the user. It is also said to be most energy-intensive in comparison to other methods. First of all the air in the greenhouse is heated to a certain temperature so that the air can hold more moisture. When the upper limit of temperature and humidity is reached the air is exchanged with cooler air from the outer environment with the help of vents and exhaust fans. The cool air that is brought inside the greenhouse unit must be compensated by heating to maintain a set temperature. It is found that when heating is delivered beneath the crop the rate of transpiration increases in plants. It is found that about forty percent of the energy supplied to control humidity is used by the plants immediately to transpire vapor in the air. Hence one can say that the relationship between heating, ventilation, and transpiration is escalating. It is one of the reasons why the ventilation procedure is an energy-intensive method. It also limits the level of humidity that can be achieved through ventilation. Read about Dehumidifiers for Grow Tents in New Zealand


Condensation is used in conventional refrigerant and compressor-based air conditioning. The air that contains moisture in it is drawn towards a cold refrigerant coil where the water condenses due to low temperature. Then the water is drained away. In this process, a saturated condition is created inside the greenhouse. This along with soil dust can be ideal for bacteria and mold to flourish. The air distribution system can be ideal for the spread of bacteria and mold throughout the unit. This is one of the big challenges in the condensation method. The condensation method is also very energy-intensive and hence the energy bills can be a worry for the user.

Desiccant Dehumidification

This method of dehumidification takes a chemical approach to the process of dehumidification. The dehumidifier unit consists of a chemical absorbent that can absorb moisture from the air. Humid air is passed through the absorbent where the moisture from the air is extracted. The dry air is then released in the environment. The desiccant material is then regenerated by heating the desiccant. This method has been found to reduce energy consumption by about 60 percent in comparison to ventilation. It also offers a better level of humidity control. There are many other advantages of the desiccant dehumidifier. The heat used to regenerate the desiccant can be used to keep the greenhouse unit warm during the winter. Sodium chloride or lithium hydride is used as the brine in the system. This brine can act as a disinfectant to reduce the bacteria and fungus within the greenhouse unit. This secondary function aids in protecting the crops from diseases. The electrical connection in the desiccant system is relatively lower in comparison to the condensation method. This helps in decreasing the electrical power consumption. Another reason for lower energy consumption in the dehumidifier system is the absence of a compressor. The main drawback of the system is the initial cost of installing the system is pretty high in comparison to other systems.

We are supplying dehumidifiers in New Zealand and its cities Auckland, Christchurch, Wellington, Hamilton, Tauranga, Lower Hutt, Dunedin, Palmerston North, Napier, Porirua, New Plymouth, Rotorua, Whangarei, Hibiscus Coast, Nelson, Invercargill, Hastings, Upper Hutt, Whanganui, Gisborne.
Contact us at info@ambale.co.nz or dial +64 22 061 7007.