Yellow Blotchy Leaves - Nitrogen Deficiency?

[ChalupaBatman]

Hey guys,

I'm growing a wedding cake autoflower (RIGHT in picture) which has slowly been lightening green. I am noticing blotchy yellow in the lower leaves as well as yellowing on the top. Compared to her neighbor (LEFT) you can see the difference in the images on how bright green she is. Both plants are feeding from an automated water tank that runs 2 times a day for one minute. I am going to replace the feed because I noticed the ph moved up higher than i had originally thought it was at.

I am unsure what the deficiency could be or if this is nutrient lockout? Tips for how I should approach to fix the issue? Thank you for the help.

Below are my stats and some pics:


Grow Environment
Place: grow tent
Start date: 3/20/23
Temp: ~ 75 degrees
Humidity: 55%
Medium: 80% coco coir 20% perlite that's been buffered
Nutes Type: currently on general hydroponics maxigro bloom 5-15-14 at 50% strength
Water Source pH: 6.4ph (I had set it to 5.9 but it seems to have moved up)
PPM: 443
Other: I have two fans running in the tent, one to create air movement, the other to exhaust

 

[Phytoplankton]

Not a coco guy, but you might try upping the feed to 3/4 or full strength, and also try to keep the PH at 5.8. If that doesn't help, then a flush and start feeding again. Let's see what @Bill284 has to say, he's one of our coco gurus.

 

[Roy Growin]

You are using bloom nutes; 5-15-14 is nowhere near enough Nitrogen at this stage, particularly at half strength

 

[Phytoplankton]

You are using bloom nutes; 5-15-14 is nowhere near enough Nitrogen at this stage, particularly at half strength

Good catch Roy, I missed the bloom nutes part. Yep, they need more veg nutes (N).

 

[Bill284]

Not a coco guy, but you might try upping the feed to 3/4 or full strength, and also try to keep the PH at 5.8. If that doesn't help, then a flush and start feeding again. Let's see what @Bill284 has to say, he's one of our coco gurus.

Hey Phyto thanks for the Tag.
Feed at 5.8 ph all day long, keep it there.
Plus your under feeding.
Feed this way.
Put calmag in your plain water first every time.
Then nutrients according to schedule, probably around 900 ppm by now.
Then very last set ph to 5.8.
Feed every day, every day! Until you get run off.
Keep your coco wet at all times.
Never let it dry.
And no plain water ever.
Do that you will be fine.
Let me know if you have questions.
Hope your doing well my friend.
Take care.




#VIVOSUN #Love What You Grow
Bill284

 

[SmokingWings]

I am unsure what the deficiency could be or if this is nutrient lockout? Tips for how I should approach to fix the issue? Thank you for the help.

As the others have pointed out you one of the first things to do is start to bump up the fertilizing rates to match a grow in a coco coir medium. And change the pH.

Was there a reason that the fertilizing ratio was dropped to 50%?

What is making this interesting is that the plant on the right is a Wedding Cake autoflower and is the one showing the yellowing of the leaves from the bottom to the top. There is no mention of the type of plant on the left nor mention of any problems with that plant. The plant on the left is also a week or more into flower so a half dose of fertilizers could be causing similar changes in the leaf color.

6.4ph (I had set it to 5.9 but it seems to have moved up)

Usually the pH of the standing water will drop and not move up. Were you measuring the water in the reservoir or measuring the water after it had run through the coco mix?

 

[ChalupaBatman]

Yeah seems I've been underfeeding is the consensus I've gotten across the board, so im up to 100%. In the past ive underfed with 2x a day watering for a skywalker kush photo and she did extremely well so I thought it would be best to replicate that process to avoid overfeeding.

SmokingWings, the plant on the left is LSD auto and yeah she seems alright. So I was measuring only the reservoir, not the run off so will have to do that.

 

[SmokingWings]

SmokingWings, the plant on the left is LSD auto and yeah she seems alright. So I was measuring only the reservoir, not the run off so will have to do that.

I was curious so I asked. Other than a way to check for nutrient levels I figure checking the 'run off' is not useful as far as pH goes. The pH before watering/fertilizing is what seems to be the most important.