The definitive answer on light green growth, please.

[CannaDana]

I need to know why, once and for all. Why is my new growth light (lime) green, when the plants seem otherwise completely healthy? Here are photos:

Here's the standard info:

Strain: Kush Mints
Medium: FF Ocean Forest Soil
Nutes: FF Grow Big, Big Bloom, Tiger Bloom, and CalMag
Cycle: This is Day 6 of transition from veg to flower.
Lights: Two bar LED lights, Growers Choice E-ROI720s, 26" from canopy, 570-720 ppfd.
Water pH: 6.3-6.4
Runoff pH: 5.9-6.0

These plants are in the beginning of stretch. My last (first) grow this also happened when I flipped the plants. Until a few days ago, these were all a nice, rich green. Now all the new growth is super light, almost lime green.

Why does this happen? Is this just the result of rapid growth, and is nothing to be concerned about? Should I hit 'em with some nitrogen?

 

[mysticepipedon]

Don't hit them with nitrogen.

Because your pH appears to be in the zone, I would guess this is just a result of rapid growth. Light is needed by the plant to form chlorophyll. The new growth hasn't been hit with enough light yet. Don't sweat it.

If this were a deficiency symptom, it would be for an immobile nutrient in the plant (as opposed to immobile in the soil). That is, the plant does not have the ability to move the nutrient from old plant parts to the young growing points. Those nutrients includes sulfur, iron, zinc and other micronutrients. N, P and K deficiencies never show up on the growing points, because they are mobile in the plant and the plant will strip the nutrient out of old leaves and send it to the young growth.

This is one of the reasons people ask to see pics of the hole plant, and not just a single leaf with a deficiency symptom.

When you have deficiencies showing at the growing points, it is often either a pH problem or lockout and not that the nutrient is missing from the soil.

 

[2Bad]

Don't hit them with nitrogen.

Because your pH appears to be in the zone, I would guess this is just a result of rapid growth. Light is needed by the plant to form chlorophyll. The new growth hasn't been hit with enough light yet. Don't sweat it.

If this were a deficiency symptom, it would be for an immobile nutrient in the plant (as opposed to immobile in the soil). That is, the plant does not have the ability to move the nutrient from old plant parts to the young growing points. Those nutrients includes sulfur, iron, zinc and other micronutrients. N, P and K deficiencies never show up on the growing points, because they are mobile in the plant and the plant will strip the nutrient out of old leaves and send it to the young growth.

This is one of the reasons people ask to see pics of the hole plant, and not just a single leaf with a deficiency symptom.

Are the plants in the back of the last picture yellowing though?

 

[mysticepipedon]

Are the plants in the back of the last picture yellowing though?

There's something happening there. Could be N.

 

[CannaDana]

Are the plants in the back of the last picture yellowing though?

Good eye!

That one plant in the upper left is a different strain that was severely damaged about 4 weeks ago, and has never completely recovered. I decided not to pull it, but instead to work with it and see if I could bring it back to life. It is still struggling, but it is alive and is trying valiantly to recover. So please ignore that one plant, as it's an entirely different situation.

 

[2Bad]

Good eye!

That one plant in the upper left is a different strain that was severely damaged about 4 weeks ago, and has never completely recovered. I decided not to pull it, but instead to work with it and see if I could bring it back to life. It is still struggling, but it is alive and is trying valiantly to recover. So please ignore that one plant, as it's an entirely different situation.

Just checking (: lol looking quite lovely

 

[CannaDana]

There's something happening there. Could be N.

As I said above, that's just one plant that got damaged and I'm trying to rescue it. Here is a photo of the lower leaves of some of the other plants. All the other plants are quite healthy with no yellowing lower leaves.

 

[PK1]

can you take the effected plant outside or just under natural light to see how it is. Right now it's so shiny that its hard to say anything imo

 

[CannaDana]

can you take the effected plant outside or just under natural light to see how it is. Right now it's so shiny that its hard to say anything imo

Wait, you want to see the affected plant? Okay, here you go. I pulled it out and shot a little video. As I said, this plant almost died, and as you can see I had to put in two supports just to keep the plant upright. But the condition of the top of the new growth makes me think I'm getting it back on track. My guess is that the yellowing old/lower leaves and the chlorotic higher leaves are because once they start to go you can't get them back. I'm hoping that the proper new growth means that's in the past. But if you think it has a mobile nutrient deficiency based on the bottom leaves, please tell me. I certainly am about the farthest thing from an expert on this.

Can you tell what deficiency this plant had/has?

And for comparison, I also shot a little video of one of the other plants that is healthy except for the light green new growth. Here it is.

Believe it or not, this is after I stripped the plant. It revealed a whole bunch of growth that had never seen the light of day. Yes, I know it needs further stripping. I was planning on doing that at Week 3 of flower. Here's a photo of what these plants looked like before stripping.

Thoughts?

 

[Homesteader]

Really healthy plant but just in need of some nutrients imo. Looks like a feeder to me. Is this photo right when the lights went on? Sometimes night growth will lack green but change in a few hours. Looks more though

 

[PK1]

@CannaDana you grow organically, correct>?

 

[steamroller]

I have been having similar issue with all my strains . Just new growth .Rest of plant is wonderful . I have not been real concerned but .
I believe it is the FFOC soil sort of ? Maybe just it's reputation ?
I think when plants are midlife the soil is void of nutrients completely . If it has any they are not at a level that does much .
I have been a little 'heavy' with my FF ferts and I have only seen improvements .
The color usually catches up in a day or so now .
I mentioned and read you add mg . I Mg 2x for every 1x Ca and feel it is needed for the plant in this soil .
I think because people have issues in the beginning with the soil they are cautious for the rest of grow .
I have been pushing rather than pulling back for what I see.