White Widow, Yellow Tips, new growth

ILGM Support Ticket:

What is the strain? — White Widow

Indoor or Outdoor? If outdoor, planted in ground or in a container? — Indoor

Size of space? — Grow Tent is 4FT by 4FT floor space, 7Ft tall.

Soil or Hydro? Type of Medium used? — Soil. Fox Farm Ocean forest.

pH? Of the soil or medium (root zone) and of the water that is fed to the plant? — Soil PH 6.6, Water I add is at PH 6.4 - 6.6.

Type of nutrients used? NPK? EC/PPM levels? — No nutes yet, due to the Foxfarm Ocean Forest soil containing nutes.

Temperature? Day vs. night temp or highest and lowest temps? Root zone temps - Tent temperature ranges from 72 F at night to 77F during the day. This is measured at the floor of the tent. Temperature at the canopy level is 75 to 80 when the lights are on during the day. My dark period is at the warmest part of the day from 10:00 to 4:00.

Humidity %? — 36% today (Outside it’s 22% today.)

Light system/watts/lumens/FLUX/PAR? — 2 300W LED’s 1 400W LED. Estimated 5k Lumens.

Number “weeks/days” from into Season, Vegetative Growth or Bloom/flowering? — Still in Vegetative Growth, 4 weeks into veg.

Yellow tipped new growth turning into dying leaves with blotched surfaces. To further confuse the issue, not every branch is having the same issue. The main stalk (new top growth) and a few of the nodes are having this issue. Otherwise, the plant seems to be growing well.

When this issue first showed, my first thought was too much nitrogen. (had that issue last grow.) But this time the leaf tips aren’t turning brown and the rest of the leaf starts to show blotches. This is difficult to see under normal light, but the LED’s really show it. When the plant is taken out of the LED lighting, only the yellow tips and the worst blotches are visible.

Yellow Tipped New Growth
Damaged leaves

Perhaps those LEDs are too close. I have read that if too close to canopy they will burn the crap out of leaves. If only the top new growth is effected, then raise your lamps until it stops showing on MacG when you need him? LOL

Wow, you can try moving the LED’s farther away, but I don’t really think that is the problem. It does look like nute burn to me, mostly, and yes sometimes the leaves can look worse under the LEDs than under more white light. I’m still thinking it is a deficiency or maybe toxicity, maybe not from pH, but maybe something else, the weird twisting and mottled splotchy look just seems to scream nutrient imbalance or pH to me, but you seem to have the pH ruled out.

Since you are using distilled water now, if I had to make a guess, adding cal-mag might help.

I’m still kind of leaning towards nute burn/toxicity/multiple overdose tho after doing some serious eye strain trying to peer into the truth in your pictures, lol…

I flushed it with sledgehammer. A gallon’s worth. Let it run out pretty much all the way. Flushed with a plain gallon of water. Let it run out pretty much all the way. I’m waiting to add nutes to give it a chance to show me something different.

Hey how’d this work out?

Sorry I didn’t get back sooner. After I let the plant rest without nutes for a week, I started back in and everything seems to be perfect now. The flush seems to be what it needed. (And a little bit of PH change. I used to shoot for 6.5, now I shoot for 6.5-6.8. Ever since that, I’ve had a lot less problems.)


Bingo!! I love this forum, its great for practicing troubleshooting others issues, especially if its like your post and i see something ive dealt wih before. Glad the flush and rest worked for you! I love seeing the learni g process, in process.:+)

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What if only the lower leaves are affected?? I was thinking I had LED burn too…but are you saying if it were light burn, new growth would be burnt too?

Without a picture or 2 I cannot proceed at guessing. Post a pik and then we might be able to give you an informed answer. : )

It looks like your pH may be off in your nutrients might be a little hot and back off on your nutrients for a few waters

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Other than what looks like some sort of debris on the top of leaf; I see nothing wrong. I am blind though, LOL Perhaps another mentor can find an issue with your plant.

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No debris, these are brown spots and yellowing leaves. I will hold off on nutes. Thanks @Hogmaster

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I’m thinking a support ticket would help. Knowing soil type, ph, etc. would be helpful I think.

COPY/PASTE: This “Support Ticket” into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, or NA

Soil in pots, Hydroponic, or Coco?

System type?

PH of runoff or solution in reservoir?

What is strength of nutrient mix? EC, or TDS

Indoor or Outdoor

Light system, size?

Temps; Day, Night

Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, No

Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you

Calcium deficiency can cause black spots to start. Do you use any Cal-Mag?