Hey guys, right now I have some kosher kush, white grapes and dynamite in coco and perlite flowering under 600w in a 4x4 tent about half way through week 7. I am having some issues with the kosher kush, it seems to be getting burnt by my light, I have my light raised as high as it will go and have pretty much tied the kush as far away from the light as I am able. I have a White Grapes which is probably 10cm or more closer to the actual light as the buds on the kosher kush which are closest to the light and it is doing just fine. I actually had the light a fair bit closer at first and the WG was still doing fine, I only raised it because the KK was struggling.. The kosher kush's leaves are undergoing significant yellowing, which seems to originate at the petioles and radiate outwards, the leaves are very dried out and in many cases they snap easily, there are also spots that have more serious light burn where they have gone brown and dry. I cannot figure out how or why this plant could be this light sensitive, when I have another plant considerably closer to the light which is thriving and have grown several other plants that were all fine that close. It is summer here and we have had some hot days, I have read kosher kush is sensitive to heat but it is not really showing the traditional heat stress signs like wilting. I feed my girls once a day and have considered that perhaps I need to water the kosher kush an additional time, but again the lack of wilting makes me think this is unlikely to be the case. The fact that the undergrowth is still green has me fairly convinced the light is an issue here. I would like to hear any alternate suggestions on what I could be dealing with and any potential solutions to dealing with it. Thanks in advance! Here are some photos, the first two demonstrate the suspected light burn I am referring to. The third one shows how well the plant that is closer to the light is doing in the same space. I should also add I have good air circulation in there, 3 fans blowing air in the grow room and beyond adequate ventilation with an intake fan as well instead of relying on passive intake. View attachment 1705415
rotten photos ...but we do what we must! .. Standard Nute Burn (SNB) cut back the nutes 50% for 2-3 weeks will delay harvest but you will get weed, to my blog: the flush! http://forum.grasscity.com/blog/1093/entry-9829-flush-baby-flush/ stay sharp with your temps and humidity and be never afraid to flush in nature its but a rain storm ..
I will take your advice, it seems nutrient burn could well be the culprit, that had seriously not even crossed my mind because I run such a low EC, always water to 20% run off at least and regularly feed just plain water. I will dial back the nutrients and see how she goes. Thanks very much mate, that really is a huge help!