Professional Marijuana Grower May-June 2019 Issue | Page 30

power strips, or light timers. The tiny lights on these de- vices may not seem like they would affect the growth of plants, but any light in the dark cycle should be consid- ered bad light. Light leaks most commonly occur around and through ventilation ports. Closely examine intakes, exhausts, and air-cooled ducting systems to ensure no light is entering the cannabis garden. Once a grower’s eyes have adjusted to the dark, it should be very easy to see any light leaks. Basically, if a grower sees anything other than complete darkness, he or she should address the areas of concern. Repairing Light Leaks Once a grower has determined where the light leaks, if any, are occurring, he or she should immediately take action to repair it. Electrical tape is a great way to cover operational lights on any electronic devices that must remain in the grow room. It may take multiple layers of tape to completely smother the light. For light leaks coming through ventilation ports or air-cooling systems, a manipulation of the ducting itself is usually the best solution. By bending the ducting upward to 90 degrees, a gardener can stop the light from entering the grow room. Light refl ects, but it doesn’t bend. Black interior ducting should be the go-to ducting for indoor horticul- turists as it negates light refl ection within the ducting. Any other cracks or holes within the grow room can be repaired with caulk or expanding foam insulation. Black Leader of Safe and Organic Products Trusted Organic Plant Protection Approved for Organic Use - made from food grade material Controls and prevents powdery mildew on contact Long-lasting benefits without leaving a residue Call Us Today! For Your Powdery Mildew Solution. safergro.com [email protected] 30 • Professional Marijuana Grower [phone] and white poly-plastic sheeting (if thicker than six mils) can be used as a black-out material and hung on walls or ceilings where light leaks are present. Check and Recheck After making the necessary repairs, a cannabis grower should go through the entire process again. Once all of the light leaks in the fl owering room have been correct- ed, a horticulturist (again waiting approximately fi ve minutes) should not be able to see their own hand during the grow room’s dark cycle. Although this may seem extreme, an indoor grower will not be able to achieve a cannabis crop’s full potential without this level of dark- ness during the dark cycle. When all else is equal, a pitch-black dark cycle will make the difference in canna- bis fl ower density and quality. Checking and maintaining the grow room’s light-tight dark cycle should be included on every indoor grower’s regular maintenance checklist. Light Tight with Air-cooled Refl ectors When using air-cooled refl ectors, getting the dark cycle to be completely pitch-black can be more diffi cult than in an indoor garden without air-cooled refl ectors. Air- cooled refl ectors generally draw air in from outside the garden space. When light from that outside source trav- els through the ducting, it reaches the refl ectors and gets refl ected into the garden space. There are a few different ways a grower can tackle this problem. One option is to draw the fresh air from another room, not directly out- side. This way, the other room can be kept dark and will not allow light to enter the ducting. Another solution is to bend the ducting at the outside source so that it creates an “s” shape. This is effective because light can refl ect, but it cannot bend. It is also helpful to use ducting with a black or dark interior. When dark interior ducting is bent in an “s” shape, the light is not able to reach the garden space. Indoor cannabis growers spend a lot of time and money to produce a high-quality, prolifi c harvest. Maintaining a light-tight, pitch-black dark cycle in the cannabis fl ow- ering room is a relatively easy and inexpensive way to make a signifi cant impact over the yield and quality of the crop. Many indoor cannabis growers, even experi- enced ones, are operating a fl owering room that, due to light leaks, is not providing the optimal environment for cannabis. When designing a cannabis fl owering room, the photoperiod, especially a light-tight dark cycle, should be a top priority. An indoor horticulturist who takes the time to address any light leaks and includes a “light-tight” test on his or her regular garden main- tenance checklist will be rewarded with larger yields, tighter buds, and higher quality cannabis. PMG Eric Hopper is a Professional Marijuana Grower Se- nior Editor. He can be contacted at [email protected]. May/June 2019