Why You Should Prevent Light Leaks in Grow Tents

One of the biggest benefits, and reasons that growers turn to indoor weed growing is the ability to create and maintain a controlled environment. This allows growers to provide, and optimize conditions plants need not only to live, but to thrive. Among the various factors to manage, lighting is one of the most critical. 

While growers often focus on the type, intensity, and duration of light, one issue that is frequently overlooked is the impact of light leaks. 

In this article, we’ll explore the causes of light leaks, why light leaks in grow tents are harmful, provide some tips on preventing light leaks, and cover the proper lighting schedules for each stage. 

What Do Light Leaks Mean to Cannabis Growers?

Light leaks refer to unintended gaps, openings, cracks, vents, or seams in a grow tent that allow external light to enter during the plants' dark period. Cannabis is highly sensitive to light cycles, and disruptions in the dark period can have some severe, unwanted consequences.

Light leaks in growing tents can interfere with the plant's natural processes and cause problems such as stunted growth, hermaphroditism, and lower yields. 

Why You Don't Want Light Leaks in Your Grow Tents

When light leaks into the controlled environment, it disrupts the plant’s photoperiod, which can spell trouble. Cannabis is highly sensitive to light, and even the slightest exposure can prevent the plant from entering its rest or dark period, interrupting its natural cycle.

Cannabis growth is controlled by its photoperiod, or light schedule. The amount of hours of light the plant receives dictates whether it's growing vegetatively (growing leaves, stems and branches) or blooming (producing flowers instead of leaves and branches). 

When light leaks into the controlled environment, it interrupts the plant's photoperiod, which can be a recipe for disaster. Cannabis is a highly light-sensitive plant, and even the faintest luminance can keep the plant awake and prevent it from entering its rest or dark period. 

Cannabis relies on its dark period for many different purposes, like:

• Rest and recovery from the energy-intensive processes of photosynthesis and transpiration;
• Transitioning from photosynthesis to respiration, which allows the plant to redistribute stored energy (carbohydrates) and hormones (phytochrome/auxins/ginberllins) to support vigorous growth and flower production;
• Root development;
• Nutrient uptake;
• Internal repairs.

hermaphrodite cannabis caused by light leaks

Inconsistent dark periods will stress the plant, increasing the risk of hermaphroditism (producing both male and female flowers). Since hermaphrodite cannabis plants grow both female flowers and male pollen sacks, they tend pollinate themselves and others. 

In my experience, if one plant hermaphrodites, it'll have some sort of negative effects on the plants around it. This leads to seed-filled buds and reduced yields. This type of stress put on the plant can also cause poor development, increased vulnerability to pests and diseases, and slow growth.

Tips on Preventing Light Leaks

There are plenty of things you can do to prevent light leaks in your cannabis grow tent. Here is a comprehensive list of tips: 

1. Use the best grow tent on the market, like the Hey abby GrowMate. Its thick, double-stitched fabric and widened light blocking zippers are designed to block all light.

2. During setup of your grow tent, turn the grow light off, close your eyes and sit in the dark for about 5 minutes to let your eyes adjust. After the dark epriod, open your eyes and check all seams, openings, vents, zippers, fans and so on, for any possible light that could be shining into the tent. If you discover any spots where light leaks, use weather stripping or heavy duct-tape to seal them off.

3. Use an additional curtain, blackout fabric, or second layer of material over your grow tent door or entry to provide an extra layer of light blocking protection. Large grow facilities will often use containment doors or chambers to act as a buffer against external light and bugs.

4. Keep external lights in your growing area off or covered. You can even set up any external lights on a smart plug to control them while you're away.  

5. Use light blocking air baffles on fans or ducting if light is getting in through your equipment. 

6. Use smart cameras to not only keep your grow safe, but also use it as an extra set of eyes any time you may be away. You would be surprised how many issues you've found in your grow tent by checking the cameras!   

7. Use green bulbed light if you need to work on the plants or in the tent while the plants are in the dark period. 

8. Use a reliable timer or controller to automate your grow light schedule.