I suspect nitrogen deficiency - Didn't see this coming

[beard o]

Man I didn't see this coming. Watered and did a round of LST on my autos on Mon. They looked great. Looked in on them yesterday, all's fine. Peeked in before breakfast today and, oh, oh!
I see a couple yellowing leaves that weren't there yesterday.
They were scheduled to be fed today. So after lunch I mixed up some Tiger Bloom, Calmag and pHed to 6.5. Open the tent and it's worse than I thought. Three of the four appear to have a nitrogen deficiency. Yellow or yellowing leaves. One plant, the smallest was unaffected.
Some have yellowing leaves moving up the main stem. So I fed them. Raised my light a bit. Soil is FFOF, light is 1000w HPS.
Will these plants survive?

 

[Absorber]

Man I didn't see this coming. Watered and did a round of LST on my autos on Mon. They looked great. Looked in on them yesterday, all's fine. Peeked in before breakfast today and, oh, oh!
I see a couple yellowing leaves that weren't there yesterday.
They were scheduled to be fed today. So after lunch I mixed up some Tiger Bloom, Calmag and pHed to 6.5. Open the tent and it's worse than I thought. Three of the four appear to have a nitrogen deficiency. Yellow or yellowing leaves. One plant, the smallest was unaffected.
Some have yellowing leaves moving up the main stem. So I fed them. Raised my light a bit. Soil is FFOF, light is 1000w HPS.
Will these plants survive?

Pictures are essential if you are looking for advice

 

[013]

Hey Beardo!

It’s designed to be a system but tiger bloom is only one bottle out of a trio of products needed to complete a grow. You still need the other 2, think they are called Grow Big and Big Bloom…

anyways it’s best to go to the fox farms website and download their feed chart for soil.

 

[Bill284]

Man I didn't see this coming. Watered and did a round of LST on my autos on Mon. They looked great. Looked in on them yesterday, all's fine. Peeked in before breakfast today and, oh, oh!
I see a couple yellowing leaves that weren't there yesterday.
They were scheduled to be fed today. So after lunch I mixed up some Tiger Bloom, Calmag and pHed to 6.5. Open the tent and it's worse than I thought. Three of the four appear to have a nitrogen deficiency. Yellow or yellowing leaves. One plant, the smallest was unaffected.
Some have yellowing leaves moving up the main stem. So I fed them. Raised my light a bit. Soil is FFOF, light is 1000w HPS.
Will these plants survive?

Good afternoon my friend.
Are you feeding the full line of nutrients?
Or just one part of a mixed nutrient schedule?
Our girls require lots of nutrients especially if they are flowering.
Any pics.


Stay safe
Bill284

 

[beard o]

here's one.

 

[AgedMaster]

here's one.

Do you have a fan on them I can see some leaves cupping a little.

 

[PotChimp]

Those leaves are pretty dark green for N deficiency. The leaf blade tips are slightly brown, too. If it were me, I'd only be giving it P for food at this point. And not much longer, either.

 

[beard o]

Those leaves are pretty dark green for N deficiency. The leaf blade tips are slightly brown, too. If it were me, I'd only be giving it P for food at this point. And not much longer, either.

the bud in the photo is under 2 weeks old.

 

[PotChimp]

That's pretty good growth for being less than two weeks old. With chemical nutrients, I'd stop feeding 10-14 days before harvest. I thought that plant was further along, but I still wouldn't give it any N. If plants that are lower aren't as bad, a part of the problem (or all of it) could be what AgedMaster said. Airflow to keep heat off the tops of the plants.

 

[beard o]

Do you have a fan on them I can see some leaves cupping a little.

yes, two clip on fans. My light source is a 1000w HPS, with a 6" inline fan attached to the enclosed reflector hood to extract the warm air from the hood. The stale warm air is vented out the top via a 6" exhaust fan on the outside of the tent, and out the window.

 

[Roy Growin]

I've run similar - I reckon an active intake is a must to keep the air fresh with HPS cool tubes
They look fine tho - what's the prob? lol

 

[SmokingWings]

Watered and did a round of LST on my autos on Mon. They looked great. Looked in on them yesterday, all's fine. Peeked in before breakfast today and, oh, oh!
I see a couple yellowing leaves that weren't there yesterday.
They were scheduled to be fed today. So after lunch I mixed up some Tiger Bloom, Calmag and pHed to 6.5. Open the tent and it's worse than I thought. Three of the four appear to have a nitrogen deficiency. Yellow or yellowing leaves. One plant, the smallest was unaffected.
Some have yellowing leaves moving up the main stem. So I fed them. Raised my light a bit. Soil is FFOF, light is 1000w HPS.
Will these plants survive?

The picture of the flowering portion looks good and doing well for two weeks old.

A photo showing the entire plant, top to bottom, will help with figuring out what is happening with yellow leaves. Being able to see the same yellowing leaves you are seeing helps with diagnosing issues.

Turn off the grow lights and use regular room lights and camera flash will give better clues as to the true color of the yellow and what might be happening. Often the color of light from the 'grow lights' changes the color of the leaf enough to fool our eyes and we end up seeing more yellow, purple, red or dark green than there really is.

Do you have the rest of the fertilizer program? The Tiger Bloom is part of a 3 bottle fertilizing system. Yellowing leaves on plants two weeks after the beginning of flowering has been a common question no matter what soil or grow medium is being used.

 

[KingJohnC]

Fan leaves function as nutrient sinks or stores where the cannabis plant can draw nutrients from older growth when building new growth. I would either be more conservative when defoliating or slightly increase the nitrogen to meet the plants current requirements. What order do you add the nutrients to water and what nutrients do you currently use?