jessie.diamond
Member
Summary of the problem:
The plants are in the third week of flowering. Over the last few weeks, chlorosis has been hitting older leaves, accompanied by necrosis. The problem starts at the tips and proceeds *unevenly* down toward the petiole. It's not interveinal, nor does it seem to attack the margins first. The fan leaves will often fall off quickly, before the problem fully develops. The plants have long internodal spacing, and they've grown much taller than expected. Put those last two things together, and the plants now look much too airy and tall, with about half the expected vegetation. There are a lot of thin leaves and not many wide leaves, too, making the whole crop look like sativas -- even though they're a mix of many strains, with plenty of Indica dominant plants.
The pictures might help the diagnosis, so I attached the small pic (800 width), and a larger one (2000 width) on File Den: http://www.fileden.com/files/2009/7/23/2518920/Top Panorama - All - 2000 Width.jpg
View attachment 1120464
I hope the pics tell the story to a more expert eye than mine. But I've also included a basic Q & A that will answer most questions about the grow (at the bottom of the post.)
I have some suspicions, such as a nutrient lockout of potassium, but I don't want to influence anyone's diagnosis. I do have all the books, I've done many different troubleshooting routines, and I've looked at hundreds of different pictures -- but so far, nothing has seemed conclusive.
TIA for your input. So far, this problem has been a toughie to solve.
~jessie
Grow Details -- The 4 "Special Notes" are factors which I think most likely to be involved in this problem.
1. Are you growing from seed or clones? Feminized seeds.
2. How old are your plants? 11 weeks.
3. How tall are your plants? 60"
----- SPECIAL NOTE #1: Way too tall, I know. Just pointing this out . . .
4. What size containers are they planted in? 3 gallon.
5. What is your soil mix? FFOF 50%, FFLW 50%, some lime.
6. How often do you water and what type of water do you use? RO water, EOD, when plants are pretty dry.
7. What is the pH of your water? 7
8. What kind of fertilizer do you use and what is its NPK ratio? Not much fertilizers for the first 8 weeks. Some PBP, Nirvana or Liquid Karma, Great White bacteria/fungi, some silica, some cal-mag. I go fairly light on everything.
----- SPECIAL NOTE #2: I've been using GH's Ph Up to get the nute water into the sixes . . . about 5ml per gallon. I think it's possible that this could contribute to a lockout?
9. Do you foliar feed or spray your plants with anything? Neem oil foliar twice over the last 8 weeks.
10. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights"): 2 x 1,000w plus 2 x 600w
11. How close are your lights to the plants? 14" away
12. What size is your grow space in square feet? 60 sq. ft.
13. What is the temperature and humidity in your grow space? 50% Humidity. Temp is 75-80 during dark, 75-77 during light.
----- SPECIAL NOTE #3: I've read the research on "DIF" (the difference between night and day temps), and my numbers aren't ideal. So, this could be a factor in the problem.
14. What is the pH of the soil? 6.5
----- SPECIAL NOTE #4: My main nutes (PBP Bloom and AN's Nirvana) drop the Ph of my RO water down into the 3.0 to 3.8 range . . . so I've been adding GH's PH UP to get into the mid-sixes. But this requires about 5ml per gallon, so the salt in the Ph UP is my guess at the third most likely factor in the problem.
15. Have you noticed any insect activity in your grow space? No.
16. How much experience do you have growing? Third full grow, give or take.
The plants are in the third week of flowering. Over the last few weeks, chlorosis has been hitting older leaves, accompanied by necrosis. The problem starts at the tips and proceeds *unevenly* down toward the petiole. It's not interveinal, nor does it seem to attack the margins first. The fan leaves will often fall off quickly, before the problem fully develops. The plants have long internodal spacing, and they've grown much taller than expected. Put those last two things together, and the plants now look much too airy and tall, with about half the expected vegetation. There are a lot of thin leaves and not many wide leaves, too, making the whole crop look like sativas -- even though they're a mix of many strains, with plenty of Indica dominant plants.
The pictures might help the diagnosis, so I attached the small pic (800 width), and a larger one (2000 width) on File Den: http://www.fileden.com/files/2009/7/23/2518920/Top Panorama - All - 2000 Width.jpg
View attachment 1120464
I hope the pics tell the story to a more expert eye than mine. But I've also included a basic Q & A that will answer most questions about the grow (at the bottom of the post.)
I have some suspicions, such as a nutrient lockout of potassium, but I don't want to influence anyone's diagnosis. I do have all the books, I've done many different troubleshooting routines, and I've looked at hundreds of different pictures -- but so far, nothing has seemed conclusive.
TIA for your input. So far, this problem has been a toughie to solve.
~jessie
Grow Details -- The 4 "Special Notes" are factors which I think most likely to be involved in this problem.
1. Are you growing from seed or clones? Feminized seeds.
2. How old are your plants? 11 weeks.
3. How tall are your plants? 60"
----- SPECIAL NOTE #1: Way too tall, I know. Just pointing this out . . .
4. What size containers are they planted in? 3 gallon.
5. What is your soil mix? FFOF 50%, FFLW 50%, some lime.
6. How often do you water and what type of water do you use? RO water, EOD, when plants are pretty dry.
7. What is the pH of your water? 7
8. What kind of fertilizer do you use and what is its NPK ratio? Not much fertilizers for the first 8 weeks. Some PBP, Nirvana or Liquid Karma, Great White bacteria/fungi, some silica, some cal-mag. I go fairly light on everything.
----- SPECIAL NOTE #2: I've been using GH's Ph Up to get the nute water into the sixes . . . about 5ml per gallon. I think it's possible that this could contribute to a lockout?
9. Do you foliar feed or spray your plants with anything? Neem oil foliar twice over the last 8 weeks.
10. What kind of lights do you use and how many watts combined? (HPS, MH, fluorescent, halogen, incandescent "plant lights"): 2 x 1,000w plus 2 x 600w
11. How close are your lights to the plants? 14" away
12. What size is your grow space in square feet? 60 sq. ft.
13. What is the temperature and humidity in your grow space? 50% Humidity. Temp is 75-80 during dark, 75-77 during light.
----- SPECIAL NOTE #3: I've read the research on "DIF" (the difference between night and day temps), and my numbers aren't ideal. So, this could be a factor in the problem.
14. What is the pH of the soil? 6.5
----- SPECIAL NOTE #4: My main nutes (PBP Bloom and AN's Nirvana) drop the Ph of my RO water down into the 3.0 to 3.8 range . . . so I've been adding GH's PH UP to get into the mid-sixes. But this requires about 5ml per gallon, so the salt in the Ph UP is my guess at the third most likely factor in the problem.
15. Have you noticed any insect activity in your grow space? No.
16. How much experience do you have growing? Third full grow, give or take.
