The Interplay Between Light, Temperature, and Humidity in Greenhouse Settings

Riya Chhabda

Greenhouses offer a controlled environment for plants, allowing growers to manipulate factors like light, temperature, and humidity to optimize conditions for cultivation.

Understanding the intricate interplay between these three elements is key to successful greenhouse gardening.

In this blog, we'll delve into how light, temperature, and humidity interact within greenhouse settings and their impact on plant growth.

1. The Role of Light

a. Photosynthesis:

Light is the energy source that drives photosynthesis—the process by which plants convert light energy into chemical energy (sugars) for growth. Different plant species have varying light requirements, with some thriving in full sun and others preferring shade.

b. Light Duration:

The duration of light exposure, or photoperiod, can influence plant development. Some plants require specific day-length conditions to initiate flowering or other developmental stages.

c. Light Quality:

Light quality, including wavelengths in the visible spectrum and beyond (e.g., UV and IR light), affects plant morphology and physiology. For instance, blue light can influence leaf thickness and flowering, while red light is crucial for photosynthesis.

2. The Impact of Temperature

a. Metabolic Processes:

Temperature profoundly affects plant metabolic processes. It influences enzymatic activity, respiration rates, and the overall speed of biochemical reactions within the plant.

b. Growth Rate:

Temperature plays a critical role in determining the rate of plant growth. Cooler temperatures tend to slow down growth, while warmer temperatures promote faster growth.

c. Stress Response:

Extreme temperatures, whether too hot or too cold, can stress plants, leading to wilting, leaf damage, or even death. Maintaining an optimal temperature range is crucial for plant health.

3. The Influence of Humidity

a. Transpiration:

Humidity impacts plant transpiration—the process by which plants release water vapor through their leaves. High humidity reduces transpiration rates, while low humidity increases them. This affects water and nutrient uptake by plants.

b. Disease and Pest Management:

Humidity levels can influence the prevalence of certain diseases and pests. Some thrive in dry conditions, while others prefer high humidity. Maintaining the right humidity level can help manage these issues.

c. Temperature Regulation:

Humidity plays a role in temperature regulation within the greenhouse. High humidity can slow down temperature fluctuations, creating a more stable environment.

The Interplay Between Light, Temperature, and Humidity

Understanding how these three factors interact is essential for greenhouse management:

  • Temperature and Humidity: When the temperature rises, the air's capacity to hold moisture increases. This can reduce relative humidity levels, potentially stressing plants. Conversely, cooler temperatures can lead to higher relative humidity.

  • Light and Temperature: Light influences temperature through solar radiation. More intense sunlight can lead to higher temperatures within the greenhouse, affecting plant growth rates and the need for temperature regulation.

  • Light and Humidity: Light affects plant transpiration rates, which, in turn, influence humidity levels. Bright light can increase transpiration, potentially reducing humidity.

Optimizing the Interplay for Plant Growth

Achieving optimal growth conditions in a greenhouse involves balancing these factors:

  • Light: Choose appropriate light levels and quality for your specific plant species. Use shading or supplemental lighting as needed.

  • Temperature: Maintain a consistent temperature range suitable for your plants. Use heating and cooling systems to control temperatures.

  • Humidity: Monitor and adjust humidity levels as necessary. Implement watering techniques, ventilation, and humidity control systems to create an ideal environment.

Ultimately, the interplay between light, temperature, and humidity is a dynamic and delicate balance that greenhouse growers must carefully manage. By understanding the nuances of these interactions and employing appropriate strategies, growers can create the perfect environment for healthy, thriving plants and a successful greenhouse operation.

Strategies for Managing the Interplay

  1. Monitoring Systems: Install climate monitoring systems that provide real-time data on temperature, humidity, and light levels within your greenhouse. These systems can help you make informed decisions and adjustments as needed.

  2. Shade and Ventilation: Use shade nets or curtains to control light levels and reduce excessive heat. Implement ventilation systems that allow for proper airflow to regulate temperature and humidity.

  3. Watering Techniques: Employ watering techniques that not only provide plants with moisture but also influence humidity levels. For instance, overhead sprinklers can increase humidity, while drip irrigation systems minimize water splashing, reducing humidity.

  4. Heating and Cooling: Invest in efficient heating and cooling systems that can be adjusted based on temperature and humidity readings. These systems help maintain a stable greenhouse climate.

  5. Humidity Control: Use humidifiers or dehumidifiers to fine-tune humidity levels as required. These devices can be especially useful during periods of extreme weather conditions.

  6. Shade Management: Adjust shading levels to control the amount of light entering the greenhouse. Automated shading systems can respond to changing light conditions throughout the day.

  7. Plant Selection: Choose plant varieties that are well-suited to your greenhouse's specific conditions. Some plants are more adaptable to fluctuations in light, temperature, and humidity than others.


The interplay between light, temperature, and humidity is a complex and ever-changing dynamic within greenhouse settings. Successful greenhouse management involves a nuanced understanding of these factors and their interactions.

By implementing monitoring systems and employing effective strategies for adjusting light, temperature, and humidity, growers can create an environment that fosters healthy plant growth and maximizes agricultural yield. The art of greenhouse gardening lies in mastering this delicate dance between the elements to create the ideal conditions for your plants.

    Subscribe to the blog

    The best source of information for customer service, sales tips, guides and industry best practice. Join us.