Humidity Levels for Propagation

Propagation is a crucial step in the life cycle of plants, enabling the production of new individuals from existing ones. Among the various environmental factors that affect successful propagation, humidity levels play a significant role. In this article, we will delve into the importance of humidity in propagation, its effects on plant growth, and the optimal humidity ranges for different stages of propagation.

Understanding Humidity

What is Humidity?

Humidity refers to the amount of moisture present in the air. It is commonly expressed as a percentage and can greatly influence the overall health and development of plants.

The Role of Humidity in Propagation

Humidity plays a crucial role in plant propagation as it directly affects several physiological processes, including transpiration, moisture absorption, and root development. Proper humidity levels create a favorable microclimate that promotes successful propagation by preventing excessive water loss and maintaining the necessary moisture for optimal growth.

Optimal Humidity Levels for Propagation

Rooting Stage

During the rooting stage of propagation, maintaining high humidity is essential to support the development of roots. The ideal humidity range for this stage is typically between 70% and 100%. High humidity levels help reduce water loss through transpiration, allowing the cutting to focus its energy on root formation.

Establishment Stage

Once the roots have developed, the cutting enters the establishment stage, where it begins to grow new leaves and shoots. During this stage, gradually reducing the humidity level is important to encourage the plant to acclimate to normal atmospheric conditions. The recommended humidity range for the establishment stage is around 50% to 70%.

Hardening Off Stage

The hardening off stage prepares the propagated plants for life outside controlled environments. Gradually exposing them to lower humidity levels helps strengthen their tissues and prepares them for the challenges of the natural environment. Humidity levels in this stage should be gradually reduced to around 40% to 60%.

Methods to Control Humidity


Misting is a common method used to increase humidity levels in propagation areas. It involves spraying fine water droplets over the plants or within the propagation chamber. Misting can be done manually or automated using misting systems that release mist at regular intervals.

Humidity Domes and Covers

Using humidity domes or covers creates a controlled environment around the cuttings, retaining moisture and raising humidity levels. These transparent structures trap humidity and reduce water loss through evaporation, creating an ideal microclimate for root development.

Fogging Systems

Fogging systems generate a fine mist or fog that fills the propagation area, ensuring consistent and elevated humidity levels. These systems are often automated and can be programmed to provide intermittent bursts of mist to maintain optimal humidity conditions.

Monitoring and Adjusting Humidity Levels

Monitoring humidity levels during propagation is crucial to ensure optimal conditions. Several tools can help measure humidity, such as digital hygrometers or humidity sensors. If humidity levels are too low, additional misting or covering the cuttings with a humidity dome can help raise the humidity. On the other hand, if humidity is too high, ventilation or reducing misting frequency can help lower the levels.


Humidity levels are a vital aspect of successful plant propagation. By understanding the different stages of propagation and their corresponding humidity requirements, growers can create optimal conditions for root development, establishment, and hardening off. Employing methods to control and monitor humidity levels allows for the creation of a favorable microclimate, enhancing the overall success rate of propagation endeavors.