Interveinal Chlorosis on top of the plants

[aimeone]

Hi guys,

I would like you to have a look at my ladies. Seems like they didn’t take the last feeding so well, which was like 5 days ago.

Let me give you some details:

Strain: kali China (ace seeds)
Mediumlagron light mix(slightly fertilized)
Potsize: 7 l (2 gallons)
Veg. Time: 35 days
Flower time: 16 days
Space: 2 ft x 2 ft
Light: 180 w led (hanspanel), 1 ft distance
Water: 25% tab, 75% destilled water
Nutes: GHE Flora (soft water)

Since I use super low fertilized soil I feed with every watering. I water with 3/4 gallons and raised the ec with every watering. Since I use led and temperature is like 23 degrees Celsius I only need to water once a week.

Last watering was with ec 1,2 and ph 6,5 with the ratio of g-m-b 1-1-1 or n-p-k 8-6-12.
For me it looks like there is maybe an imbalance of K-Ca-Mg which leads to a mag deficiency. The plants only show the symptoms on top part of the plants. Bottom leaves are still fine. I could even imagine there is an excess of potassium since I saw an illustration with similar symptoms, which are for example:
- new leaves grow thin blades
- new leaves develop interveinal chlorosis

The symptoms appeared after last watering.
I would really like to hear about your theory and welcome every hint.

 

[Pinkfan]

Is your led too close. Sorry i cant help i am learning myself

 

[slownickel]

Hi guys,

I would like you to have a look at my ladies. Seems like they didn’t take the last feeding so well, which was like 5 days ago.

Let me give you some details:

Strain: kali China (ace seeds)
Mediumlagron light mix(slightly fertilized)
Potsize: 7 l (2 gallons)
Veg. Time: 35 days
Flower time: 16 days
Space: 2 ft x 2 ft
Light: 180 w led (hanspanel), 1 ft distance
Water: 25% tab, 75% destilled water
Nutes: GHE Flora (soft water)

Since I use super low fertilized soil I feed with every watering. I water with 3/4 gallons and raised the ec with every watering. Since I use led and temperature is like 23 degrees Celsius I only need to water once a week.

Last watering was with ec 1,2 and ph 6,5 with the ratio of g-m-b 1-1-1 or n-p-k 8-6-12.
For me it looks like there is maybe an imbalance of K-Ca-Mg which leads to a mag deficiency. The plants only show the symptoms on top part of the plants. Bottom leaves are still fine. I could even imagine there is an excess of potassium since I saw an illustration with similar symptoms, which are for example:
- new leaves grow thin blades
- new leaves develop interveinal chlorosis

The symptoms appeared after last watering.
I would really like to hear about your theory and welcome every hint.

Looks like the soil went acidic.

 

[AgentPothead]

I think a potassium deficiency would show in older leaves first not newest growth. You didn't mention your PH, which 9 times out of 10 I feel like PH is the issue, causing lockouts.

 

[aimeone]

Not talking about the deficiency, I was talking about an excess of potassium. Found an illustration which says exactly that.

I watered with a ph of 6.5 but didn’t check the runoff yet.

 

[redlaser]

I would take a gallon of water check it’s ph/ec, pour that into plants container, might not need the whole gallon. Add enough to get a 2-3 cups worth to drain through.
Check the runoff ph and EC.
Ideally you would capture the middle amount of water passing through, and not use the very beginning of the runoff to get an average number. I would also test the total amount of water to see how different it is.
If you could take a typical/average amount of the soil mix, not a top or side of the root ball, like an inch worth, add a known quality(ph/tds tested)water, not much more than twice the amount of soil sample, you can test that as well. Compare to runoff, probably won’t be that different, but easy enough to do.

edit; I was too slow with my runoff info, lol

 

[AgentPothead]

Alright yeah and the bottom left there says the soil has probably gone acidic, like slownickel mentioned. Definitely check the run off PH cause 6.5 should be perfect for soil.

 

[aimeone]

I just watered one of the plants with ph 6.2 and 750 ppm. Runoff was 6.2 and 850 ppm. So I guess ph is ok but does the increased ppm mean that there is a salt buildup?
I also figured out that the other plants which have the problem got fed with only 500 ppm. Could maybe been a little to less for that stage right?

 

[TanzanianMagic]

Hi guys,

I would like you to have a look at my ladies. Seems like they didn’t take the last feeding so well, which was like 5 days ago.

Let me give you some details:

Strain: kali China (ace seeds)
Mediumlagron light mix(slightly fertilized)
Potsize: 7 l (2 gallons)
Veg. Time: 35 days
Flower time: 16 days
Space: 2 ft x 2 ft
Light: 180 w led (hanspanel), 1 ft distance
Water: 25% tab, 75% destilled water
Nutes: GHE Flora (soft water)

Since I use super low fertilized soil I feed with every watering. I water with 3/4 gallons and raised the ec with every watering. Since I use led and temperature is like 23 degrees Celsius I only need to water once a week.

Last watering was with ec 1,2 and ph 6,5 with the ratio of g-m-b 1-1-1 or n-p-k 8-6-12.
For me it looks like there is maybe an imbalance of K-Ca-Mg which leads to a mag deficiency. The plants only show the symptoms on top part of the plants. Bottom leaves are still fine. I could even imagine there is an excess of potassium since I saw an illustration with similar symptoms, which are for example:
- new leaves grow thin blades
- new leaves develop interveinal chlorosis

The symptoms appeared after last watering.
I would really like to hear about your theory and welcome every hint.

It looks very much like the iron deficiency/lockout as shown in Ed Rosenthal and J.C. Stitch's Marijuana Garden Saver.

"Note that Fe deficiency looks similar to a Mg deficiency except for it's location."

https://wegrowapp.com/wp-content/up...utrient_and_Deficiency_Table_-_RQS_Blog-7.png

Notice the damage is concentrated at the growing tips (non-mobile nutrient deficiency, like iron), and the death of the leaf tips moving up from the tip of the leaf. Iron gets locked out at a high pH.

--

Now there is more going on.

- First, light mix doesn't have enough nutrients in it for growth. It is great for mixing into a supersoil, where you add bloodmeal, bonemeal, woodash, magnesium lime, lava meal for N, P, K, Mg/Ca, and trace elements, respectively.

See The Rev's book True Living Organics for a great description of the nutrient content of many organic substances.

- Using liquid nutrients only makes it tougher to keep the plant continuously fed, while solid nutrients feed the plant slowly but continuously.

- Pot Size

You should use 1 gallon per expected foot of growth. So if you're growing a plant which would normally be 6 feet, you need a 6 gallon container to avoid running into nutrient deficiencies. With large containers, you also water/feed less, which improves stability of pH and EC within the medium.

Basically large root systems (P) allow a lot of nutrients to be taken up from the soil, and fat stems and branches (K) allow a lot of those nutrients to be transferred to the leaves and flowers.

- Insects

Judging from the small and large holes in the leaves, it is likely there is some kind of insect activity, most likely a leafhopper. Leafhoppers look like small spiders or flies, yet what they have in common is that when you get near them, they jump away for some distance. They feed from the tops of the leaves. For that, 2 treatments with drops of pyrethrum (chrysanthemum derived), vegetable oil and (organic) dish or liquid soap (just enough to dissolve the oil into water) is enough.

Insects can exacerbate mild nutrient deficiencies.

- What's needed by the plant and when

For leaf, stem and root growth, you need:

Mg - leaves, phototropism and general leaf health and responsiveness.
P - roots
K - stems and branches

For the growth phase (which should be mid-late flowering if you're growing weed for the flowers, instead of the stem/fibre, or seeds).

Except for nitrogen, these are non-mobile nutrients that become part of the plant's cell and cannot be moved - you need more of them when a lot of cells are being made, like during fast growth in flowering:

N - for the growth phase in general

Ca - cell structure, especially during massive growth
Su - smells/terpenes, which help plants distract insects
Si - the stuff resin is made of, cell structure, deters insects, fungi

Trace Elements - all kinds of functions, for instance Mo turns nitrates into ammonium within the plant. Various trace elements are very important in cannabinnoid formation and help determine the potency of the end product.

 

[slownickel]

I just watered one of the plants with ph 6.2 and 750 ppm. Runoff was 6.2 and 850 ppm. So I guess ph is ok but does the increased ppm mean that there is a salt buildup?
I also figured out that the other plants which have the problem got fed with only 500 ppm. Could maybe been a little to less for that stage right?[/QUOTE

Your pH is too low. Half a gram of calcium hydroxide (quick lime) will raise the pH to 7 or so. Do one plant.

 

[aimeone]

Hi guys, just to keep you updated. Things are developing slowly. Symptoms but also the buds :/
First of all thanks for all your support here. I’m still not really sure what I’m dealing with.
The weird thing is, symptoms are now turning out exactly the same as in my two last grows which makes me wonder if it is really something with my led light and the aggressive spectrum. Somehow everything starts as soon as i switch to the flowering mode on my panel. Only this time seems symptoms appear later, but also I switched the mode later in flowering stage. I already read that led panels with mostly blue and red Chips tend to roast plants and well, if I switch to the flowermode there is a lot of red led‘s.
What supports my opinion is, that right now I’m having two totally different types of grow in my run.
1. organic soil with organic fertilizer (biobizz)
2. Mineralic soil (plagron) and mineralic fertilizer (general hydroponics)

Both ways are showing the kind of the same symptoms. I find that super suspicious.

Definitely was the last time growing under these led‘s and maybe I’ll buy a hps soon to finish the run.

@slownickel: anyway I have another question about the ph. Today I read a part of the „famous“ Lucas which is saying optimum runoff should be 1300 ppm at ph 5.8. what is better and why?