Yellow stripes, crispy leave, discolouration.

[WeedyBoyWonder]

Hi all, we have 2 plants under a 400w HPS.
They are being given Bio-Bloom nutes, in the correct doses.
The water is at around PH 5.5-6.5, 2 liters every 3 days.

It will be 30 days into flowering tomorrow, but over the last few days the leaves are beginning to get yellow 'burn' like stripes.
This is only on one plant specifically.

I hope the pictures attached will show what I am talking about, any information as to what can be done to prevent more of this and what the problem is would be much appreciated.

1st picture - the 2 plants.
2nd/3rd/4th pictures - the problem, yellowing.
5th picture - Lower fan leaf on the OTHER plant, strange discoloration??

WeedyBoyWonder Reviewed by WeedyBoyWonder on 07-09-2007. Yellow stripes, crispy leave, discolouration. Hi all, we have 2 plants under a 400w HPS. They are being given Bio-Bloom nutes, in the correct doses. The water is at around PH 5.5-6.5, 2 liters every 3 days. It will be 30 days into flowering tomorrow, but over the last few days the leaves are beginning to get yellow 'burn' like stripes. This is only on one plant specifically. I hope the pictures attached will show what I am talking about, any information as to what can be done to prevent more of this and what the problem is would Rating: 5

[stinkyattic]

Light burn.
Tie the plants a little further from the light, or raise it.

[WeedyBoyWonder]

hey man, thanks for a quick reply.
Are you sure that is light burn? I raised the light to the top (as high as it will go) when I first noticed the problem, and its not 35cm away from the top of the plants.
I just mad some fan adjustments so its flowing RIGHT in between the light and plants, but I don't think it's just down to heat. Check out the last picture, deffinatly not light burn.

[stinkyattic]

What are your temps at the canopy, and at the soil surface? Light burn and heat stress very often go hand in hand, and heat stress will make the symptoms of nute burn much more severe. You are right, the last pic is not light burn, it looks like fert burn.

[WeedyBoyWonder]

The temp at the soil is around the 80's, and at the canopy 90's.
We know this is reallllllly high, but cannot put in extractor or a/c.

[the image reaper]

sorry, I'm not seeing 'light burn' there ... not good photos, but it looks like some magnesium deficiency goin' on there ... I know temps are ideal at 75, but my cabinet is in the 90's almost always (it's 105 outside, today), and never any visible heat damage ... ya might do a good pH check on your run-off (soak the hell out of it with 7.0 water, then measure the first bit of run-off) ... this is a good link for plant problems: International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles! Disclaimer: I am NOT an expert, and have a history of using drugs :jointsmile:

[BUZz UK]

sorry, I'm not seeing 'light burn' there ... not good photos, but it looks like some magnesium deficiency goin' on there ... I know temps are ideal at 75, but my cabinet is in the 90's almost always (it's 105 outside, today), and never any visible heat damage ... ya might do a good pH check on your run-off (soak the hell out of it with 7.0 water, then measure the first bit of run-off) ... this is a good link for plant problems: International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles! Disclaimer: I am NOT an expert, and have a history of using drugs :jointsmile:

thanks man,

i had a feeling it was some sort of deficiency andy...

We need to use my sisters cam for some better quality pics...

[stinkyattic]

When I've seen Mg deficiency it manifests as paler green striping rather than white.
If that's Mg def, you have had a deficiency for a long time and didn't catch it in the early stages, and your temps are contributing to the white appearance of those necrotic patches.

[the image reaper]

When I've seen Mg deficiency it manifests as paler green striping rather than white.
If that's Mg def, you have had a deficiency for a long time and didn't catch it in the early stages, and your temps are contributing to the white appearance of those necrotic patches.

I WAS WRONG very sorry :wtf: ... I should have said a magnesium overdosing, rather than 'deficiency' ... I suspected that, because of this Plant Problem Guide paragraph :...


QUOTE : "One of the worst problems a person can have is a magnesium def caused by a ph lockout. By giving it more magnesium to cure the problem when you are thinking you are doing good, but actually you are doing more harm then good. When the plants canâ??t take in a nutrient because of the ph being off for that element, the plant will not absorb it but it will be in the soilâ?¦ therefore causing a buildup. A buildup will be noticed by the outer parts of the plant becoming whitish and or a yellowish color. The tips and part way in on the inner leaves will die and feel like glass. Parts affected by Magnesium deficiency are: space between the veins (Interveinal) of older leaves; may begin around interior perimeter of leaf. " UNQUOTE: ...

I saw the 'whitish' reference, but didn't realize I was looking at the 'over-nuting with magnesium' paragraph ... I feel so cheap, and un-worthy

[BUZz UK]

so what do we need to do to fix this guys? My mother won't be happy if we kill 2 of her babies...