Understanding Under-Canopy and Side Lighting for Cannabis

Posted by

July 22, 2025

On February 11, 2024

Table of Contents

Cultivating cannabis is both an art and a science, requiring a deep understanding of the plant’s needs to produce the best possible yield. Among the critical factors for optimal growth, lighting plays a pivotal role. In this comprehensive guide, we’ll dive into the specifics of under-canopy and side lighting for cannabis, exploring their benefits, how to implement them correctly, and answering some common questions to help you maximize your grow tent’s potential.

How Far Should Light Be From Canopy Cannabis?

image for your article, focusing on an indoor cannabis grow setup with side and under-canopy lighting. This visual emphasizes the strategic lighting placement for optimal growth during the flowering stage, without including any words and ensuring it aligns with the detailed description provided.

The Crucial Balance

Finding the perfect distance between your lights and the cannabis canopy is like walking a tightrope—it requires precision and balance. Too close, and you risk light burn, stressing your plants and potentially stunting their growth. Too far away, and your plants may stretch towards the light, leading to weak, leggy growth. The ideal distance varies based on the type of light you use:

visually represent the crucial concept of finding the ideal distance between grow lights and the cannabis canopy, illustrating the balance needed to avoid light burn and prevent stretching, all without the use of words.

LED Lights: 12-24 inches. LED lights are cooler, allowing them to be placed closer to the canopy without the risk of heat stress.
HID Lights (HPS/MH): 18-36 inches. These lights run hotter, necessitating a greater distance to prevent heat damage.
Fluorescent Lights (T5/CFL): 6-12 inches. These emit the least heat, allowing them to be placed closer to the plants.

Adjusting as Plants Grow

image featuring an indoor cannabis grow setup with LED lighting strips placed under the plants, highlighting the effectiveness of under-canopy lighting. This setup showcases the strategic use of LED strips to ensure the lower canopy receives ample light for optimal growth during the flowering stage.

It’s not a “set it and forget it” deal. As your cannabis plants grow, regularly adjusting the light distance is crucial to maintain the optimal light intensity across all stages of growth.

Does Under Canopy Lighting Work?

Shining Light on Hidden Growth

visually showcase the effectiveness of under canopy lighting in an indoor cannabis grow setup, illustrating how this technique illuminates and promotes growth in areas that would otherwise remain shaded and underdeveloped.

Under canopy lighting refers to placing lights beneath the plant canopy to illuminate areas that top lighting does not reach. This technique can significantly enhance growth by ensuring lower branches and leaves receive sufficient light, promoting a fuller, more uniform development.

It’s particularly beneficial during the flowering stage, where maximizing light exposure can lead to increased bud production. Growers can place lights under their plants and on the side of their tents for the best Under canopy lighting.

This extra lighting can control dark spaces that my be shaded around your plant. These shaded spots can produce fluffier buds, while using side lighting can grow much denser buds on your plants from top to bottom.

Implementing Under Canopy Lighting

visually depict the strategic positioning of small, low-heat LED lights beneath the cannabis canopy, targeting dark areas to ensure balanced growth without overheating, emphasizing the careful monitoring of temperature and humidity in the grow environment.

Positioning: Place small, low-heat lights, such as LEDs, beneath the canopy, targeting dark areas, such as under the plant, and dark sides of your growing tent or grow room.
Balance: Ensure the additional light does not overheat your plants. Monitoring temperature and humidity levels is key.

Is Side Lighting Good for Cannabis?

visually highlight the impactful role of side lighting in a dense indoor cannabis grow setup, showcasing how adding light sources to the sides of the grow space enhances light exposure to lower branches, promoting balanced growth and potentially higher yields.

Expanding Light Reach

Side lighting for cannabis is a game-changer, especially in dense grow setups where light penetration can be a challenge. By adding light sources to the sides of your grow space, you can increase light exposure to lower branches, encouraging more balanced growth and potentially higher yields.

Benefits of Side Lighting

Improved Yield: By illuminating more of the plant, side lighting can increase flower production, especially in the lower parts that top lighting misses.
Enhanced Growth: Side lighting promotes more even growth, reducing the need for extensive pruning or training.

Choosing the Right Lights for Side Lighting

LED strips or compact fluorescents are ideal for side lighting due to their low heat output and flexibility. Position them to target the mid to lower sections of your plants for the best results.

What is Side Lighting in a Grow Tent?

image created showcases the strategic placement of side and under-plant LED lighting strips in an indoor cannabis grow setup, emphasizing their installation at various heights to ensure even coverage and optimize growth, all while preventing overheating with their low-heat output.

Optimizing Your Grow Tent’s Potential

In the confined space of a grow tent, maximizing light exposure is crucial. Side lighting in a grow tent involves strategically placing additional light sources around the sides of the tent to complement your main, overhead lighting. This setup ensures that all parts of your cannabis plants receive adequate light, crucial for a healthy and productive grow.

Setting Up Side Lighting

image illustrates the strategic selection and positioning of LED strips and compact fluorescent lights for side lighting in an indoor cannabis grow setup, emphasizing their placement around the mid to lower sections of the plants to optimize growth and development with their low heat output and flexibility.

Strategic Placement: Install side lights at different heights to target various parts of the plant, ensuring even coverage. Your top lighting will do fine to cover the tops of the plants so you will want to place any side lighting below the canopy lighting to have the best effects. Some growers will even place LED lighting strips under their plant to help reduce airy buds.
Light Selection: Opt for low-heat options like LEDs to prevent overheating in the enclosed space of a grow tent. LED lighting strips work great for this as they are small and easy to place around your flowering plants.

Monitoring and Adjustment

Regularly check your plants for signs of light stress or burn, and adjust the positioning of side lights as needed. It’s all about finding the right balance to provide your plants with the best possible light coverage without causing harm.

Boosting Flowering Yields with Side and Under-Canopy Lighting

images created depict the meticulous process of monitoring and adjusting side and under-canopy lighting in an indoor cannabis grow setup, focusing on a grower's efforts to ensure optimal light coverage and prevent stress or burn.

When cannabis plants enter the flowering stage, their light requirements change. This stage is crucial for yield, making efficient light distribution more important than ever. Properly implemented side and under-canopy lighting can significantly impact the quantity and quality of your harvest.

Best Time to Add Side and Under Lighting for Cannabis

Additionally, the illustrations highlight how these lighting strategies enhance the flowering stage, boosting yields and improving the quality of the harvest, all conveyed through careful visual storytelling without words.

We recommend adding side lighting once you switch your cannabis plants into their flower stage. This means turning the lighting back indoors to 12/12 hour of lighting to induce flowering in your cannabis plants. You can also wait a week into flowering without any noticeable different in flowering weight after your cannabis plants have finished flowering.

Side Lighting: A Flowering Boost

image illustrates the optimal timing for adding side and under lighting in an indoor cannabis grow setup, capturing the transition to the flowering stage with a 12/12 hour light cycle. It visually conveys the strategic addition of side and under-canopy lights to enhance flowering, aligning with the guidance for timing these lighting adjustments to optimize the flowering process and potential yield.

During flowering, cannabis plants can greatly benefit from additional light sources. Side lighting serves as a powerful tool to ensure that lower buds, which are typically shaded and less developed, receive enough light to grow and mature properly. This can lead to:

Increased Bud Density: Light reaching the lower branches encourages denser, more substantial bud formation.
Higher Overall Yield: More light exposure results in more photosynthesis, directly influencing the plant’s ability to produce flowers.
Improved Quality: Adequate light can improve cannabinoid and terpene profiles in the buds, enhancing potency and flavor.

Under-Canopy Lighting: Unleashing Hidden Potential

image showcases the beneficial impact of side lighting on flowering cannabis plants, visually demonstrating how side lighting illuminates and promotes the growth and maturation of lower buds that are typically shaded, capturing the significant flowering boost provided by this strategic lighting approach.

Under-canopy lighting is particularly effective during the flowering stage for similar reasons. By illuminating the lower parts of the plant that receive less natural light, you can:

Boost Lower Bud Growth: Lower buds develop more fully, contributing to the overall yield.
Increase Energy Efficiency: Light is delivered directly to areas that need it most, reducing waste.
Promote Plant Health: Better light distribution helps prevent mold and mildew by reducing humidity in the lower canopy.

Implementing for Flowering Success

image illustrates the transformative effect of under-canopy lighting on flowering cannabis plants, highlighting how this strategic lighting technique illuminates and promotes the growth of lower parts of the plants, effectively unleashing their hidden potential during the crucial flowering stage.

To maximize the benefits of side and under-canopy lighting during flowering, consider the following tips:

Timing: Introduce side and under-canopy lighting as you transition your plants to the flowering stage to immediately support their changed light needs.
Intensity and Spectrum: Use lights that offer a spectrum tailored for flowering, often with more red wavelengths, to support bud development.
Adjustment: Monitor plant response carefully. Adjust the positioning and intensity of your lights to avoid stress while ensuring adequate coverage.

Optimizing Light Placement for Flowering Cannabis

image visually represents the careful timing, intensity, and spectrum adjustment of side and under-canopy lighting in a cannabis grow setup transitioning to the flowering stage. It highlights the introduction of lighting tailored for flowering, with a focus on red wavelengths for bud development, and showcases a grower fine-tuning the setup to ensure optimal plant growth and health.

Best Practices for Side Lighting for Cannabis

Side lighting plays a critical role in illuminating areas that the main overhead lights can’t reach effectively, especially during the dense flowering stage. Here are key strategies for placing side lights:

Mid-Level Focus: Position side lights to target the middle section of your plants. This area tends to receive less light as the canopy thickens but is crucial for developing a significant portion of your yield.

image visually illustrates the strategic positioning of side lights in an indoor cannabis grow setup, with a focus on illuminating the mid-level section of the plants for balanced growth. It showcases the even distribution of lights for uniform coverage and highlights the use of adjustable mounts or hangers, allowing for the adaptation to the plants' evolving light needs as they grow and develop buds.

Uniform Coverage: Distribute side lights evenly around the perimeter of your grow space to ensure all sides of your plants receive balanced light. This uniform coverage helps prevent uneven growth and promotes the development of buds throughout the plant.
Adjustable Height: As your plants grow and buds develop, their light needs may shift. Use adjustable mounts or hangers for your side lights, allowing you to raise or lower them to target specific areas that require more light.

Strategic Under-Canopy Lighting Techniques

Under-canopy lighting addresses the lower sections of your plants, which are prone to being shadowed by the upper canopy. Proper placement can enhance light penetration to these lower areas:

image showcases the effective implementation of under-canopy lighting in an indoor cannabis grow setup. It illustrates the strategic placement of lights directly beneath the main canopy to illuminate shadowed areas, emphasizing even spacing for comprehensive coverage without causing hotspots or plant stress. Additionally, it highlights the importance of maintaining a safe distance between the lights and plant foliage to prevent heat stress or light burn, with a focus on using LED strips or bars for their low heat output.

Direct Underneath Placement: Install under-canopy lights directly below the main canopy, focusing on areas that receive little to no direct light. This can help stimulate growth in lower buds, contributing to overall yield.
Spacing for Coverage: Ensure that lights are spaced appropriately to cover the under-canopy area evenly. Avoid clustering lights too closely, which can lead to hotspots and potential plant stress.
Avoid Direct Contact: Keep a safe distance between the lights and plant foliage to prevent heat stress or light burn. LED strips or bars are ideal for this purpose due to their low heat output.

Adjusting for Optimal Performance

image visually represents the meticulous process of monitoring and adjusting side and under-canopy lighting in an indoor cannabis grow setup. It highlights a grower observing the plants for signs of light stress and the use of dimmable lights to fine-tune intensity for optimal plant health. The concept of periodic reevaluation is also depicted, showcasing the adjustment of lighting to meet the evolving needs of developing buds, all conveyed through careful visual storytelling without words.

Monitor Plant Response: Watch how your plants react to the added side and under-canopy lighting. Signs of light stress, such as bleaching or curling leaves, indicate the need for adjustment.
Fine-Tune Light Intensity: If possible, use dimmable lights to adjust the intensity based on the stage of flowering and plant response. This flexibility can be particularly beneficial in managing the delicate balance between light saturation and stress.
Periodic Reevaluation: As buds develop and grow, their light needs may change. Regularly assess and adjust your lighting setup to ensure that all parts of the plant continue to receive optimal light exposure throughout the flowering phase.

Conclusion: Lighting the Way to Success

image symbolizes the successful incorporation of under-canopy and side lighting techniques in cannabis cultivation, depicting a thriving and lush indoor grow space. It showcases the vibrant growth and health of the plants under optimal lighting, conveying a sense of achievement and the encouragement to experiment with lighting setups for the best cultivation results.

Incorporating under-canopy and side lighting techniques into your cannabis cultivation strategy can significantly impact your plants’ growth and yield. By understanding and implementing the principles outlined in this guide, you can optimize your grow space, ensuring every part of your plant thrives. Remember, every cannabis grow is unique, so experiment with these lighting techniques to find what works best for your setup. Happy growing!

FAQ Table

Question	Answer
How often should I adjust the light distance?	Regularly, as plants grow and develop.
Can under canopy lighting cause overheating?	It can if not monitored. Use low-heat lights and monitor temperature.
Is side lighting necessary in all grow setups?	Not necessary, but beneficial for dense canopies or larger setups.
What type of lights are best for side lighting?	LEDs or compact fluorescents due to their low heat output.

Quick Tips List

image visually encapsulates the essential strategies for effective lighting in cannabis cultivation, showcasing the adjustment of light distance for growing plants, the use of low-heat lights under the canopy, experimentation with light placement, regular checks for light stress, and the optimization of light coverage with side and under-canopy lighting. It highlights the strategic management of lighting to ensure the health and productivity of the cannabis plants, all conveyed through visual storytelling without words.

Monitor Plant Growth: Adjust light distance as your plants grow.
Use Low-Heat Lights for Under Canopy: To prevent overheating.
Experiment with Light Placement: Find what works best for your setup.
Regularly Check for Light Stress: Adjust as necessary to avoid damage.
Optimize Light Coverage: Use side and under-canopy lighting to reach all parts of your plant.