Top Leaves turning White / Yellow

alleversun · Jun 17, 2007

Hi my plants have been yellowing uncontrollably. I have grown a few times successfully but i cant seem to figure out the problem. I dont think it is a nutrient problem. I am feeding them the pH adjusted 2-part formula from Optimum Hydroponix. I am using Pro-Mix soil with a very little bit of dolomite lime. I am growing in an apartment bedroom with 1000watts HPS sog style with about 50 plants. I've never grown this many plants before and i think ventilation could be the problem. I keep the windows open for passive ventilation. I have a feeling the problem could be lack of fresh CO2 or O2. Is this possible?

thank for the help guys

here are the pics:

gmanwho · Jun 18, 2007

That may be heat stress. Find some pics and see if the match.

have any fans running? How fars the hood from the tops?

B-safe

VanGrow · Jun 18, 2007

looks like it could be a virus..........check your soil for pests.....and or root issues.....
VG

alleversun · Jun 18, 2007

i am using fans, and the tops are 2-3 ft from the lamp. i dont think its heat stress cuz the yellowing is coming from the middle of the leaves rather than the edges.

what would you recommend to fix a possible virus. the soil looks fine however. what should i be looking for? insects in the soil?

Core · Jun 18, 2007

got better pics plz ....shut of that HPS and take some new pics ...maybe it will help alot in visual aid !!

VanGrow · Jun 18, 2007

dude ...that isnt heat stress....heat stress burns the leaves.....makes them bend and crinkle....isnt light stress either....ive grown for quite a while....any time i have had yellow streaks like that...i had bugs or root issues..( root rot from over watering) ....... i personally just am geting over some gnats ....took hold big time in a few of my plants that i over watered trying to baby them....well i fucked them up.......now gnat larva.( white lice)in the root zone 100s of em.....that was 10 days ago...now one of my plants (which is recovering nicely) has a yellow streak on a new top leave....just like yours but on the side....not a nute def........in my case i am sure that the damage to the roots exposed some common pathogens to my plant due to the breakdown of the root tube etc it couldnt fight it off......if its bugs they are hard to see but considering those plants are gonna die if that progresses i would suggest taking the worst one and taking it out of the pot gently and giving it a complete once over ...... gotta look real close ...ove some roots .....use a little trich microscope if you got one......to me it looks like mosaic virus......do you smoke cigs? ......if so ...near the plants.....or does the tobacco air make its way in the room.......i would guess because you are growing so many plants your not aware of everything in every plant....like you would be with 10 plants....either way that problem WILL kill them....in all frankness they are kinda fucked now if they are in bloom....in the future dont add lime to pro mix either...it has it added to it and is ph ed for you.......could be a ph issue.....would have to be way off....promix doesnt go way off...but hey....who knows

Anyone else wanna chime in???????????
Its a cannabis emergency..............

Pro mix web site
http://www.premierhort.com/eProMix/index.htm

above l...has all the info on pro mix....
keep us posted.......

oh and......windows open will bring bugs for sure...........(edit)
VG

Blackvelvet · Jun 18, 2007

What ph are you using after adding the ferts to the water? How much dolomite lime did you add to the promix? Have you tested soil ph?

How to test soil ph: After watering and ferting well till runoff, wait 30 minutes. Apply a small amount of distilled water till you get about 1 ounce of runoff. Catch this on a saucer. Test ph. If after watering/ferting and waiting 30 minutes you can tilt the pot and get some liquid out, you can test that instead.

Charles Xavier · Jun 18, 2007

Greetings alleversun

Welcome to the infirmary (if you are indeed new); welcome back (if you are not).

I confess: I had the opportunity to respond first to your post when submitted yesterday, but I felt it prudent to refrain from casting my opinion (so soon). Certainly a consensus among cultivators is ideal and at the very least a diversity of hypotheses would suffice and perhaps eventually consensus would build....but let us nip this in the bud, (pun intended) shall we?

The visual symptoms correspond with Iron 'deficiency'.
(Also: The medium is over-fertilized and the plant (first image) displays signs of Magnesium deficiency) These elements in tandem, suggest a pH that is out of range (too high), probably due to Calcium hardness.

If you would like specific information pertaining to Iron deficiency/lockout or would appreciate further substantiation of my position...I could provide it.

Remedy: Flush, Fertilize (appropriately), Facilitate (maintain pH and the other environmental factors)

(I believe I've coined a new turn of phrase: The three (3) F's...Fancy that).

Sincerely,
Charles.

p.s. An aside: Being that this form of communication is impersonal, I find it difficult to accurately assess, if dominance or monopoly/hegemony is being manifest. This factored significantly in my decision and fueled reticence with my opinion. It is not my desire to be 'the sole authority' and if this is the impression that one is left with...then I apologize profusely. I respect every member's well-intentioned contributions to the forum.

(I trust that if my presence becomes too overbearing, a private message will shortly ensue)

p.p.s. Core has the right of this...better resolved images would have helped immensely.

C.X.

bergerbuddy · Jun 18, 2007

YUP!! Thats an IRON def!!

You need to get that PH going right to make it available to your plants... f

Make sure your root zone is not TOO COLD.. below 60 (i'm sure its not)and get the PH around 6.1 in since you have added lime. Your PH is too high and IRON is not being uptake! once things start greening up... move PH to between 6.3-6.7 move it around with waterings..

Check to make sure your fert is IRON EDTA OR EDDA Use a fert with IRON EDTA or EDDA

Peace and love..

BB

VanGrow · Jun 18, 2007

alleversun · Jun 19, 2007

VanGrow said:
....in all frankness they are kinda fucked now if they are in bloom....

so there really is no hope for them now that they are flowering?

flushing and fertilizing wont help at all? so should i scrap it all and start over? anyone feel this is the only option also?

Core · Jun 19, 2007

hold your horses dude dont do nottun stupid yet.....but for the second time ...can you plz add better pics...turn out that HPS and take a few 'natural' shots'

all we can do now is guess...dont get me wrong i like 2 guess but most of the time it will be false......but i will guess specially for you if you like .....i think....yea ..i think...i think its micronutrient lockout...lol that sounded a little sarcastic but ey dont mind me dude ..safe those plants

ohw yea you need 2 take soils ph ...its not that you ph you feddings/water that you soils ph is correct...VERRY IMPORTANT!!

and .... is the meter callibrated or old?

VanGrow · Jun 20, 2007

Allv.......dont toss em ....i never suggested that....by fucked .i meant ..like ..that sucks.....your yield will be less than spectacular..... I would take cores advice....---- someone with a gallery full of pics who really grows pot....i would also take a good look at THE reason for your nute def.....i think the "reason" is just as important as the cure....so it doesnt continue to happen.... look in your soil too....
JMO
Good luck man...
VG

alleversun · Jun 20, 2007

sorry for taking so long to post the pics...

so any further visible diagnostics u can see?

thanks again for all the help.

alleversun · Jun 20, 2007

also i did check the soil. but no visible bugs that i can see. the windows have insect screens on them too.

and for flushing just water them heavily with pH water and let the water drain off? is that it?

Blackvelvet · Jun 20, 2007

Blackvelvet said:
What ph are you using after adding the ferts to the water? How much dolomite lime did you add to the promix? Have you tested soil ph?

How to test soil ph: After watering and ferting well till runoff, wait 30 minutes. Apply a small amount of distilled water till you get about 1 ounce of runoff. Catch this on a saucer. Test ph. If after watering/ferting and waiting 30 minutes you can tilt the pot and get some liquid out, you can test that instead.

Answer the questions and test soil ph.

Guest · Jun 20, 2007

I used to do a lot of the sick plants on OG.....

I have to admit.... while it doesnt happen often enough...

Its iron def......

So I applaud the dianosis.... from our friends....

One main clue is seeing the chlorosis at the grow points including the top....

the chlorosis can be quite abrupt....

and normally you find some fairly green normal tips and chlorotic interior leaf parts....

the reason is than iron isnt mobile...

when the plant is manufacturing leaves it simply runs out and the chloroisis is the result.....

cause may be high ph....

Brother_Monk · Jun 20, 2007

Good call ChuckyX!

Iron is an important component of plant enzyme systems for electron transport to carry electrons during photosynthesis and terminal respiration. It is a catalyst for chlorophyll production and is required for nitrate and sulfate reduction and assimilation.

Iron (Fe) deficiency

Pronounced interveinal chlorosis similar to that caused by magnesium deficiency but on the younger leaves.

Leaves exhibit chlorosis (yellowing) of the leaves mainly between the veins, starting with the lower and middle leaves.

Caused by factors that interfere with iron absorption of roots: over irrigation, excessive soluble salts, inadequate drainage, pests, high substrate pH, or nematodes. This is easily corrected by adding an iron supplement with the next watering.

Fe is unavailable to plants when the pH of the water or soil is too high. If deficient, lower the pH to about 6.5 (for rockwool, about 5.7), and check that you're not adding too much P, which can lock up Fe. Use iron that's chelated for maximum availability. Read your fertilizer's ingredients - chelated iron might read something like "iron EDTA". To much Fe without adding enough P can cause a P-deficiency.

Note that when adding iron to the solution, it is often necessary to not use fertilizer for that watering. Iron has a tendency of reacting with many of the components of fertilizer solutions, and will cause nutrient lockup to occur. Read the labels of both the iron supplement and the fertilizer you are using before you attempt to combine the two.

:ying:

bergerbuddy · Jun 20, 2007

bergerbuddy said:
YUP!! Thats an IRON def!!

You need to get that PH going right to make it available to your plants... f

Make sure your root zone is not TOO COLD.. below 60 (i'm sure its not)and get the PH around 6.1 in since you have added lime. Your PH is too high and IRON is not being uptake! once things start greening up... move PH to between 6.3-6.7 move it around with waterings..

Check to make sure your fert is IRON EDTA OR EDDA Use a fert with IRON EDTA or EDDA

Peace and love..

BB

Like I said!!

And thank you to all that have ALSO diagnosed this problem.. now... lower ur PH like suggested... u will see SOME GREENING UP TOO!! and NEW GROWTH WILL BE GREEN... This is the CLUE is working... the new growth greening!!

polesitter · Jun 21, 2007

ive been lurking on this topic and i would like to thank you all for diagnosing my plant with a magnesium defiecency

Top Leaves turning White / Yellow

New member

Well-known member

Member

New member

Quality Control Controller

Member

Member

Member

Canna Coco grower

Member

New member

Quality Control Controller

Member

New member

New member

Member

Guest

Brother_Monk

Canna Coco grower

New member