Best Grow Room Conditions to maximise growth and yield | Light (PAR), Temperature, Humidity and Air

Summary

This video offers a comprehensive guide to optimizing grow room conditions for maximum plant yield. It emphasizes the critical role of light, suggesting an ideal level of 800 micromoles per square meter per second. The video also covers temperature control, recommending a range of 25 to 30°C for optimal growth and using fans for temperature regulation. It advises on maintaining CO2 levels for enhanced growth and discusses humidity management, suggesting reducing it during the flowering stage to prevent bud rot. The script simplifies complex concepts like VPD, encouraging viewers to focus on light and temperature as foundational elements for a successful grow room.

Takeaways

• 🌱 Photosynthesis is the key process for plant growth, and it's influenced by light, CO2, temperature, and moisture.
• 💡 Light is the driving force for photosynthesis; more light up to 800 micromoles per meter squared per second can lead to increased growth.
• 🔎 The optimal light intensity varies by type of grow light: fluorescents need 100 watts per square foot, high-pressure sodium around 50 watts, and high-efficiency LEDs about 35 watts.
• 🌡 Temperature plays a crucial role in photosynthesis rates, with an ideal range of 25-30°C (77-86°F) for maximum growth.
• 🍃 Proper ventilation is necessary to maintain CO2 levels and prevent heat stress, which can inhibit plant growth.
• 🌡 Nighttime temperatures should be kept above 12°C (54°F) to protect plants from cold shock.
• 🌿 CO2 levels can be increased for higher light intensities to boost growth, but it requires a closed system with sensors and canisters.
• 💦 Humidity is important for plant health, with higher humidity being beneficial up to a point, but it needs to be managed to prevent bud rot.
• 🌬 Controlling humidity involves managing air intake and extraction, and possibly using air conditioning to reduce moisture.
• 📊 VPD (Vapor Pressure Deficit) is a concept that relates temperature and humidity, with an ideal range for indoor growing being around 25-30°C (77-86°F) and 70-80% humidity.

Q & A

What are the key factors that affect photosynthesis in a grow room?

The key factors affecting photosynthesis in a grow room are light, CO2 levels, temperature, and moisture.

How does light intensity impact plant growth?

Light intensity directly correlates with growth rate up to a point. After reaching an average power of about 800 micromoles per meter squared per second, increasing light intensity does not proportionally increase growth rate.

What is the optimal light level for maximum yield?

The optimal light level for maximum yield is around 800 micromoles per meter squared per second.

How can one achieve the optimal light level in a grow room?

To achieve the optimal light level, one should check the grow light's data sheet for average part light delivery or use rules of thumb based on the type of grow light: 100 watts per square foot for fluorescent lights, 50 watts per square foot for high-pressure sodium lights, and 35 watts per square foot for high-efficiency LEDs.

What is the role of temperature in plant growth?

Temperature controls the rate of photosynthesis. The optimal temperature for growth is around 28°C (82°F), above which plants experience stress and below which the growth rate slows down.

How can temperature be controlled in a grow room?

Temperature can be controlled using fans to bring in cool air from outside, variable speed fans with temperature control, or additional heating or air conditioning with thermostat control.

What is the significance of CO2 levels in a grow room?

CO2 is essential for photosynthesis. Increasing CO2 levels can lead to marginal increases in growth rate, but for significant increases, a closed system with controlled CO2 levels is required.

How can one elevate CO2 levels in a grow room?

CO2 levels can be elevated using mushroom bags, yeast canisters, or by taking air from occupied spaces. For higher levels, a closed system with CO2 canisters, sensors, and automatic valves is required.

What is the recommended humidity level for optimal plant growth?

A relatively high humidity of about 70-80% is generally good for optimal growth, but it should be reduced to around 50% during the middle to late stages of flowering to reduce the risk of bud rot.

How can humidity be controlled in a grow room?

Humidity can be controlled by bringing in more fresh air, extracting air more quickly, covering water sources, or using air conditioning to drop humidity levels.

What is vapor pressure deficit (VPD) and why is it important?

VPD is a relationship between temperature and humidity in the grow room. Maintaining an optimal VPD range, which is around 25-30°C (77-86°F) with a relative humidity of 70-80%, is beneficial for plant growth.

What should be the first step in optimizing a grow room for maximum yield?

The first step should be to ensure optimal light levels, as it is the foundation for achieving good yield.