Brown Spots on leaves

Discussion in 'Sick Plants and Problems' started by faderharley, Apr 23, 2010.

  1. I am midway thru week 8, and some of my leaves have light brown spots on them. I spray the folage every other day w/distill water. My grow system is an Aeroponic-Hydroponic system using large CFLs lights. The lights are 4-5 inches from the top of the plant. I use flora grow, and flora micro, and I always mix it on the weaker side to prevent burn, root lockout. I drain my solution every 7 days and refurbish with fresh distilled water, and I even flush my roots for 24 hours before adding a new dose of nutreints and flor grow. Are my leaves possibly being burnt due to the spraying of folage? Any advise will help
     
  2. Whats your PH? Are you using cal/mag?
     
  3. Well that looks like a pH problem or Calcium def. to me, which is something that I'm currently dealing with. I've never grown aero/hydro so I'm not exactly sure on the pH that Calcium would get locked out at, but that could be something to check.

    If you are spraying your leaves with distilled water are you doing it when the lights are on? Water on the leaves can have a magnifying glass effect where it will burn the spots where droplets collect if they are left in the light right after spraying. You should always put the plant in the dark after you spray liquid on the leaves until whatever you sprayed has been absorbed or evaporated.

    That said, your spots look more like a pH/Calcium issue to me, but I thought I would mention the magnifying glass effect also since you are spraying the leaves.
     
  4. Agreed on the calcium def, looks like rust spots to me. Ph is first thing to check, it might be very low. Calcium locks out around 5.2 and lower in hydro I believe.

    If ph is OK then supplement your water with CalMag. The damage will continue for a bit even after treatment so be patient and know that you have some leaf loss on the way :mad:

    The magnifying effect of spraying really only applies to HID lights (MH/HPS). Personally I don't believe in misting - it's just not needed at all. Treating a problem or applying a treatment is OK for misting/spraying, but otherwise it's not needed. In nature there is nobody to baby them like that ;)
     
  5. Ph is at 6.0-6.1, but really bounces around towards the end of a 7 day cycle before I drain and replenish w/ distilled water. I add my flora micro, flora grow after 24 hours, but this time I added CaMg+ as recommended during the rinse. Thanks
     
  6. Thanks for info, I won't spray the plants while the lights on, got some CaMg+. Will try that as well. I read many times for hydro the ph is to be between 5.5 to 6.0. I keep as close to 5.8-6.0
     

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