What's new
  • Happy Birthday ICMag! Been 20 years since Gypsy Nirvana created the forum! We are celebrating with a 4/20 Giveaway and by launching a new Patreon tier called "420club". You can read more here.
  • Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!

Every cycle plants start to yellow at mid flower

I have been having the same problem every flower cycle at about 3-4 weeks.
I have a veg room with mothers and upcoming clones that never has any problems, but when they go into flower they start to look sickly a few weeks in, and leaves yellow in blotchy irregular patterns eventually turning completly yellow.

I am growing in promix in 7 gallon smartpots using floranova at around 800ppm. I'm not sure whats going on here so any suggestions would be great.
I make sure to let the soil dry out between watering so i dont think it is root rot, but maybe nute lockout?
 

RubeGoldberg

Active member
Veteran
got a few questions to sorta get the ball rolling.

1. how often are you feeding compared to watering.
2. how tall and how long were they vegged before you flip them in to flower?
3. Whats your PH going in and whats the PH of the runoff?
4. What type of soil?
5. how long does your strain usually take to finish.

Sometimes (even with lockouts) the plants will flourish in veg but when they fully transition in to flower they have different requirements and also become more susceptible to stresses.

What may be happening is a PH imbalance causing an inefficiency of uptake for the nutrients most desired when the plants are reaching their highest need for them.
So while your veg plants flourish due to their different needs, your blooming plants find themselves unable to uptake the quantities of nutrients they need.
 
@rubegoldberg thanks for the reply

1. i feeding every other watering feed/water/feed/water

2. These plants were a month or two old, topped several times.

3. PH of tap water going in is 7.0 , going out it is 6.0 (only checked the runnoff of a few plants)

4. Promix BX

5. 8 weeks

I should mention that I have had a small root aphid problem a year ago that was treated with imidicloripid. Since then I haven't seen any bugs in the soil. The ones I had were tiny though, so maybe i have them again but just cant find them.

I did notice that the runnvoff tds was high around 1100 ppm with 140ppm tap water going in. so maybe ur right about lockout

Ill try to post pics soon.
 

Andyo

Active member
Veteran
exactly the same

exactly the same

I have 4 1kw bays in a perpetual 12/12 plus seperate 2 kw veg n mothers room i have just found root aphids after trying to figure what i thought was mag deficiency .
35 yrs of growing never had root aphids,since finding them there appears to be an epidemic world wide.
im getting some carbaryl(acetylcholine inhibitor) stops them eating .
will let you know how it goes.A
 

prince kali

Member
I have been having the same problem every flower cycle at about 3-4 weeks.
I have a veg room with mothers and upcoming clones that never has any problems, but when they go into flower they start to look sickly a few weeks in, and leaves yellow in blotchy irregular patterns eventually turning completly yellow.

I am growing in promix in 7 gallon smartpots using floranova at around 800ppm. I'm not sure whats going on here so any suggestions would be great.
I make sure to let the soil dry out between watering so i dont think it is root rot, but maybe nute lockout?

pix!! everything else is speculation. are the leaves dark green apart from blotches? letting the soil dry out is not the way. its a common mistake and hurts/kills the fine roothair especially when being ferted afterwards..
soil should always be at least damp..
more help when pix... :)
 

RockyMountainHi

I'd rather laugh with the sinners than cry with th
Veteran
I should mention that I have had a small root aphid problem a year ago that was treated with imidicloripid. Since then I haven't seen any bugs in the soil.

I was about to ask if you had any little black flying fuckers....



You do know that they only grow wings when they have over run the plant they are in? That's the sign they are not only present but in MASSIVE numbers and sending out egg carrying explorers to over run the world.

If you run continious harvest - you will need to re-apply to plants in veg to stop infecting them
 
Here are some pics of the plants
 

Attachments

  • IMG_20110627_220202.jpg
    IMG_20110627_220202.jpg
    115.2 KB · Views: 14
  • IMG_20110627_220055.jpg
    IMG_20110627_220055.jpg
    57.7 KB · Views: 14
  • IMG_20110627_220020.jpg
    IMG_20110627_220020.jpg
    113.3 KB · Views: 12
  • IMG_20110627_220004.jpg
    IMG_20110627_220004.jpg
    112.3 KB · Views: 12
  • IMG_20110627_215807.jpg
    IMG_20110627_215807.jpg
    98.8 KB · Views: 15

RubeGoldberg

Active member
Veteran
With promix you should be feeding lower, 6.3 average.

The fact that you're starting at 7.0 and its going to 6.0 makes me wonder

If you started at 6.3 would it still come out at 6.0 or would it come out in the mid fives?

Its possible you have a bit of a salt buildup causing a lockout. I'd recommend feeding/watering as close to 6.3 as you can get.

When you water or feed, do you get a reasonable amount of runoff in a given week?
 
Thanks for the replies, I flushed several containers with RO water 20ppm, the runoff was an average of 1100 ppm, one runoff sample was out of range for my tds pen.

So I would assume nute lockout is my problem. I think it may be because i dont allow for enough runoff when watering. I try not to over feed them but i guess im not flushing them out enough.
 
Do you switch to low N Bloom feed when you flip? To me it looks very likely low N as it is moving old growth to new, and affecting the whole leaf. I feed Veg form thru at least 3 weeks flower and stopped having this same type issue Give a good shot or more of hi, N, couldn't hurt! :)
 

prince kali

Member
Thanks for the replies, I flushed several containers with RO water 20ppm, the runoff was an average of 1100 ppm, one runoff sample was out of range for my tds pen.

So I would assume nute lockout is my problem. I think it may be because i dont allow for enough runoff when watering. I try not to over feed them but i guess im not flushing them out enough.

another reason to go organic...
although i doubt that you overfeed them.

they look hungry!

keep your ph up! good soil buffers it perfectly...
:tiphat:
 

Crush

Member
Here are some pics of the plants

Ok what's happening is you are under watering your plant. You're soil is very loose, which causes your soil to evaporate liquid very quickly. When there's no moisture, the plant can't eat and eventually goes to it's own leaves for energy pulling the moisture and food out of its reserves.

Get a moisture meter from Wal Mart or Home Depot for like $5 and stick it in the soil. You might be very surprised how dry your soil is. You may need to do daily watering.

Remember, hydro plants and bubble systems have the roots constantly wet with liquid all the time. So don't ever let the soil dry out.

Keep the soil wet all the time and get that moisture meter.

Also when you begin to feed, do NOT feed at 800ppm with every other watering! I suggest 500ppm and then just water. Daily if you have lose soil.
 

max_well

Member
hmmm....
I would look real close for root aphids.. I know it's challenging to pop them out of smart pots to inspect the root mass, but do your best to get down in there at be real patient in good light looking for some mini crawlers. If you find some, then you can stop guessing about the phantom deficiencies. In my experience, the damage can become significantly apparent right at the stage of flower your in, and can look similar to the yellowing you're seeing. best of luck and please update us on what you find out as your grow develops.
 
bobo bolinski, I know what you mean about the transition period , floranova bloom works pretty good in veg and bloom. Although I think I have a nute lockout situation because my runoff is 1100-1650 in different containers using 20ppm water.

prince kali, I am thinking of switching to organic, it would fit my grow very well because I dont have the best system to collect runoff. Also I love the simplicity of it, only problem is I think my water has chloramine in it so I will have to get a filter.

crush, You might be right, maybe the water is evaporating to fast and leaving behind salts to suck the nutrients out of the plant through ionic bonds. I have had root rot problems in the past, so now i wait until the pots are light to pickup. They are 7gal smart pots so they stay wet for a couple days, but I dont get much runoff so maybe all the roots are not saturated.

max well, I am searching everyday because this does seem like root aphids they were doing great right up until a week ago and then now look like shit. I have grown many many cycles without problems so this is bothering me. I will get out the magnifying glass tomorrow.

I think it could also be because i vegd these plants for longer than normal without thinking about the fact that the longer veg means there could be more salt buildup than normal. Or maybe I didnt put enough lime in to account for the longer growing period. Usually I have better results when I dont ph my water using promix and lime.
 
D

driftersmokinjo

I grow in promix bx as well. I have had the problems you desribe. In my case it was ph lock out.
How it was explained to me : Promix is a soil less medium. So it needs to be treated like hydro in the ph department. 5.8 ph is your target. Promix has lime mixed in for a buffer. When I do run of test the ph is the same coming out that it is goin in. Here is a lil chart that was passed along to me when I had this problem. Hope this helps.:tiphat:
picture.php
 

pearlemae

May your race always be in your favor
Veteran
I agree with BOBO it looks like a lack of N, not necessarily a lock out but the plant self consuming in order to provide energy to the flowers. Feed a higher N for a while as he said.
In my experience when the lower leave yellow first its a lack of, rather than lock out.
 
D

driftersmokinjo

I agree with BOBO it looks like a lack of N, not necessarily a lock out but the plant self consuming in order to provide energy to the flowers. Feed a higher N for a while as he said.
In my experience when the lower leave yellow first its a lack of, rather than lock out.
No disrespect intended but he has a super high ppm already :tiphat:
 

Bush Dr

Painting the picture of Dorian Gray
Veteran
Heat stress due to poor ventilation, small flowers too ....

What extractor set up have you got?
 
driftersmokinjo, I am going to get a new ph meter and start keeping better track of what they are being fed, I have a feeling this is a big part of my problem.

pearl mae, I was thinking about giving it a strong dose of N, but I need to clean all the salts out first. I picked up a bottle of clearex and it seems to be flushing out lots of old nutes.

Bush dr, I am running my rooms sealed right now and I was thinking that maybe Im having problems because they are not getting fresh air. They get 1000ppm c02 and the veg plants are doing fine - so probably not.

I am using a magnum xxl 8 vented hoods, 1k Veg and 4k flower room have a 12'' inline fan that exchanges air back and forth between the rooms. Both rooms are cooled with a 2 fan chiller, c02 from a generator, two dehumidifiers. The rooms stay about 80F and 55% humidity. I try to keep the lights high enough so that the canopy stays nice and cool. Also have two box fans and two wall mounted fans and an 8" canfan and filter for scrubbing air.

Ill try to post some updated pics tonight, hopefully they will be able to finish half-way alright.
 
Top