Splotchy brown leaves, curling a bit.

[BatmanPetersenc]

I wonder if I've possibly over fed. Or too much light. Here are the details on the grow:

First time growing. I've helped take care of a grow before, but only as a vacation waterer and random helper.

So here are the details.

The environment:
2'x4' MH tent
MH TS2000 light (w dimmer knob, at about 95%, 14-18 inches from canopy. Photone says 700-1000PPFD, but just with my phone's sensor so I'm doubtful on those numbers)
AC infinity 6" ex fan (vented to lung room currently, though pushing it to other room shortly)
Fan under canopy, above canopy, and above light
Hisense 5L dehumidifier (just added)
~10x10 Lung room (very much not sealed from rest of basement)

The nutrients:
Tap water, PH'd roughly to 6-6.5 on a (once) calibrated bluelab pH pen. :)
FFOF soil
Fox Farms Happy Frog dry amendments (6-4-5) (every 30 days on veg., At about 1/2 - 3/4 recommended dose)
Royal gold crown Jewels Bloom (?-?-?) (Every 10-14 days at about 1/4-3/4 rec. dose.)
2x 5 gallon cloth pots
2x 7 gallon cloth pots

The grow:
homegrowncannabisco seeds
2 outdoor (1 grand daddy purple, 1 lavender)
4 indoor (2 GDP 1 LAV)

The problem:
The two indoor Grand Daddy Purples have been showing signs of a nutrient deficiency, nutrient burn, lockout, light burn or something for several weeks. Got a bit worse in flower. I water when the topsoil is dry, the pots feel light, and at least 2 days has passed between watering. Honestly, i kind of smack the pots to tell if they feel dry. They have a light feel to the hand.

Anyway, a few pics of the current status of the problem are below. The front two plants are the GDP in question in the group shots. My questions are: cause of leaf spots? Let it ride through end of flower (~4 wks in, 6 wks left)? Calmag/nutrient change? Raise light/lower intensity? Daily watering at this point? Should I trim the splotchy leaves, maybe waiting until I see good new growth? Will these leaves cause rot in this plant or others in the tent? It is super tight in there.

Thanks y'all in advance!

 

[BatmanPetersenc]

Ok, so to clarify, my questions re:

Nute deficiency?

Treat or finish flower? (Middle of week 5 flower)

Potential for bud rot or cross contamination to other plants in closet?

Thanks y'all, sorry for long first post

 

[IamN2pot]

Sorry no one has answered you and welcome to THCFarmer! I've had the same issue in soil, that's why I clicked onto your thread. I never fully solved the mystery, but what I did do was to give the plant a good flush and after it dried out, begin a 1/2 rate liquid feeding schedule. That seemed to stop the progression of that leaf spotting, and as you know, those leaves dry out and get crumbley. If I had to guess, I'd say I had a nute lockout that triggered the problem leaves, but that's just my suspicion.
I'm sure others will be along to share their helpful experiances with you.
N2

 

[GNick55]

one thing is light stress, have to re read your thread again as there might be a lockout or deficiency..

 

[GNick55]

one thing is light stress, have to re read your thread again as there might be a lockout or deficiency..

calcium deficiency

 

[growsince79]

Back of the lights

 

[BatmanPetersenc]

Thanks everyone for the thoughts! I've been out of town for ten days with a plant sitter doing the watering. They are still alive, definitely locked out.

Light intensity was lowered to about 75-80% for the last ten days, and the leaves progressed in their decay, so i don't think it is light burn.

I top dressed with Royal Gold Bloom before leaving, so if it was just low in nutes it should have bounced back, which leads me to think deficiency via nutrient lockout.

If that is the case, then would a flush be advised with 3 weeks left (from manufacture recommended harvest time)? Or final top dress and let it ride 'til amber?

I just watered and will deal with some cleaning up tomorrow. Pics below of two worst, and whole tent.

Thanks again for y'alls input!

 

[GNick55]

Thanks everyone for the thoughts! I've been out of town for ten days with a plant sitter doing the watering. They are still alive, definitely locked out.

Light intensity was lowered to about 75-80% for the last ten days, and the leaves progressed in their decay, so i don't think it is light burn.

I top dressed with Royal Gold Bloom before leaving, so if it was just low in nutes it should have bounced back, which leads me to think deficiency via nutrient lockout.

If that is the case, then would a flush be advised with 3 weeks left (from manufacture recommended harvest time)? Or final top dress and let it ride 'til amber?

I just watered and will deal with some cleaning up tomorrow. Pics below of two worst, and whole tent.

Thanks again for y'alls input!

View attachment 1262960View attachment 1262961View attachment 1262963

raise your damn lights!

 

[BatmanPetersenc]

raise your damn lights!

Not to sound offended here, but salt begets salt. But thanks for the comment.

That said, I did lower their intensity to about 75% from about 95%. And use a PAR app to verify the reduction in DLI/par. (Though i don't believe the numbers themselves, i was verifying the % reduction overall).

And the lights are at the top end of the manufacture recommended height. (@~75% Intensity).

So if light burn (or did you mean heat stress? High DLI?) is the issue, I've reduced the intensity and let it ride for ten days. If that doesn't cross light stress off the table, then I'd appreciate it if you could either re-read my update or help me understand why my changes wouldn't have had the same effect as "raising the damn light".

 

[IamN2pot]

raise your damn lights!

GNick, perhaps you could word your advice a little more ...civil? just a thought....
Batman, here is a link to a very good and informitive artical on lighting overdose. I hope it will explain and connect the dots between to much light and the nute lockout you are seeing.
I hope that helps. N2

 

[BatmanPetersenc]

Thanks

GNick, perhaps you could word your advice a little more ...civil? just a thought....
Batman, here is a link to a very good and informitive artical on lighting overdose. I hope it will explain and connect the dots between to much light and the nute lockout you are seeing.
I hope that helps. N2

Excellent article, thanks. Is the reduction of intensity by using my dimmer not sufficient? I did check leaf temps w a infrared thermometer, they were around 74*-78* F.

I can certainly raise my light though. Thank you both for that perspective, and the link was quite helpful.

Edit: light raised 2-3 inches, still at about 75%. Bedtime for the plants. Thanks again!

 

[Shaded_One]

Although @GNick55 response may seem harsh he is correct - look at your leaves. The leaves closest to the top of the canopy are the ones being impacted which 90% of the time is a lighting or heat issue. These new LED's also drive/increase the demand for Mg so I might recommend supplementing with Epsom salts every couple of weeks.

Also check your watering - those pots look DRY as hell.

 

[BatmanPetersenc]

Oh yes, they were getting watered every other day in my 10 day absence and so are very dry. There have been many learning moments in this process, so thanks to all! They'll be getting a top dress, more frequent watering, and slightly higher lights for the next bit. About to learn the art of the loupe.

Followup questions then are:

Should I remove spotted leaves? How about spotted sugar leaves? Is there risk of bud rot if they crisp up into the buds?

Thanks again! And no disrespect meant @GNick55 ! Input genuinely appreciated!

 

[GNick55]

Oh yes, they were getting watered every other day in my 10 day absence and so are very dry. There have been many learning moments in this process, so thanks to all! They'll be getting a top dress, more frequent watering, and slightly higher lights for the next bit. About to learn the art of the loupe.

Followup questions then are:

Should I remove spotted leaves? How about spotted sugar leaves? Is there risk of bud rot if they crisp up into the buds?

Thanks again! And no disrespect meant @GNick55 ! Input genuinely appreciated!

it’s all good, i’m sorry for sounding harsh which i see now is easily understandable, though i had to get up for work in 3 hrs so probably a bit kranky,..

 

[GNick55]

trust me light stress is a lot of your issue..

 

[Shaded_One]

Lights are the primary driver for EVERYTHING else. So chances are your plant is/was slightly underwatered, stressed, not given enough nutrients - and then you came home and blasted them with intense light for a few days and voila here we are. That's my guess anyways!

 

[BatmanPetersenc]

Lights are the primary driver for EVERYTHING else. So chances are your plant is/was slightly underwatered, stressed, not given enough nutrients - and then you came home and blasted them with intense light for a few days and voila here we are. That's my guess anyways!

Thanks for the reply! Lights haven't been increased since I lowered them to 75-80%, ten plus days ago. Watering happened in schedule in my absence, ~2 liters every two days. Likely under watered but hoping to avoid an overwatering situation. Idid top dress before leaving 10 days ago, and they are due. Also getting close-ish to harvest. Going to look tomorrow and see what trichomes look like.

I just completed a defoliation of the worst of the crusty fan leaves. There were some sugar leaves that looked crusty but were soft-ish, which had me the most concerned. I don't want bud rot at this stage. Hence a fairly thorough defoliation.

They look quite beautiful now, but i know their secret, and i think i agree about light burn/light stress. So, lights at 18", ~75% on the dial.

Will monitor and maybe just ride on plain PH'd water until harvest. Or top dress. Shoot, who knows. Thanks all!

 

[BatmanPetersenc]

So, fwiw in case someone stumbles on this thread with similar symptoms:

Light stress does indeed seem to have been the culprit. I was measuring PAR with the photone app and it was reading pretty high, but I doubted my phone's sensors and trusted the manufacture recommended hang heights. Raising the lights 2-4 inches and lowering intensity just a touch brought my par down to around ~600-700 (from ~850-1000). That seems to have stabilized things and allowed me to fight gnats for another few weeks and finish the grow.

 

[BatmanPetersenc]

Hello! So last grow finished up fine, maybe chopped a week earlier than ideal, but there ya go.

The clones i took around 6/16 are now about ready to flip to flower and show some similar signs. My lights have been at or below 50% the whole time. Right now they are at ~45%, 18-20 inches from canopy. PPFD reads around 180-200 with photone app, and DLI is reading around 10-12.

Any thoughts on the light settings or the small anomalies below are welcome. I'm inclined to top dress with my veg nutrients (a little Nitrogen for stretch, Happy Frog 6-4-5) and start flower in a week.