I have four feminized LA Confidential in a 4x4 area with a 1000 Watt MH. The heat does get up to 100 degrees ( i know it's too hot but I don't have a choice for now, I can only get my 6" fan next month, wich I hope will help the heat). It does get down to 70degrees at their nighttime. But I don't think that the heat is the nature of my problem. The one plant in question is 5weeks old. Started fertilizing 3 weeks ago. At that point the plants really loved the nutes. Started with 1/4 solution (of my week one schedule) for 2 feedings, 1/2 solution for 2 feedings, and then 100%. five days ago she started getting orange tips pretty much all over the plant, and on one leaf in particular there is alot of orange on the outer part of the leaf. 3 days ago I flushed my plant and stopped all nute, thaught I maybe overfertilized, but I see no improvents and it looks like some other leaves might get the same. The last pic was taken 2 days after the others. Is this a over nute problem or a deficiency of a nutrient? If I overnuted, how long before I start up the nutes again? Will the orange turn back to the color green if I can fix the problem. Thanks ahead for your advice
100 degrees is too hot, but it doesn't look like they are burning. It does look like a nutrient burn because it is sticking around the tips. If it is, you should hold off on nutes I would say at least a week, but probably 2. I usually wait until the plant looks like it has deficiencies (slight yellowing or losing some green) and then I feed them to avoid overfeeding. Nute burn is permanent and won't go away, but you will get plenty of new leaves and these ones will still be good.
great advice above I agree ..since you already flushed ...continue a few plain waterings then start at 50% again. Watch for yellowing on lower leaves, or when the stems get a little red...then it's a good time to start feeding. The leaves won't repair them selves..just keep an eye on new growth. I don't see much heat stress at all..but it will be better to lower them a little.
They are probably burning because the water in the soil is evaporating before the plant can take the nutes up...go with less nutes and more frequent watering
The effects of over-heating can be more subtle than burns and other physical symptoms. It affects the absorption of nutrients into the roots, and the ability of the plant to metabolize those nutrients. Therefore, the plant can stress out. I agree with the aforementioned posts. Also, some high-RPM computer fans will go a long ways to push some of that hot air around if you can't do anything drastic until next month. Please consider the advice these people have given you, they are smart cookies. hope that helps.