Day 45 Flower: Necrosis on fan leaves - Boron Def or Manganese Tox?

Hey ya'll

Here on day 132 since germ, day 45 of flower and one of my lovely ladies is starting to exhibit some signs of nutrient issues. I noticed the attached pictures on my middle plant only (which I believe to be Bruce Banner - photo fem'd from ILGM). I know I pumped these babies a bit hard with nutes so not too concerned about the burnt tips.

I only noticed these ailments today, although I must say it's quite hard to get a good look at the middle plant. I would believe these symptoms started to occur in the past 3-5 days. Besides the visible symptoms, the leaves are also a little brittle (not overly brittle, but I believe more than they should be).

My partner has had the VPD out of whack the past two days, having not enough humidity with the high temperatures. I suspect this could be the culprit, or just overall higher temps. Being these plants are so tall (compared to the others) they also get some tough love from the two fans we have in the corners. A lot at play here.

Nutrients:
Lotus Bloom. Lotus Boost. GH Calimagic
Currently on a W-F-W-F schedule. For the first 4 weeks of flower it was just W-Bloom+calmag(-W-Bloom (repeat). The past two weeks, however, I stopped the calmag and added the boost on a W-Bloom+Boost-W-Bloom+Boost both full strength to 2.9EC.

Medium:
PromixHP amended with Dr Earth 4-4-4 and EWC along with EWC topdress

Water:
pH on water and feed days targeted starting at 6.9 4 weeks ago and dropping to 6.7 as of now (Lotus nutrients recommend 6.5-6.8 ).

Lights:
Lights are Mars Hydro TSL2000 with 2 helper 20W LED Flood Lamps on each side of the light.

Temp/RH
Temperatures have been 81-88 lights on, 78-81 lights off
Humidity has been 63-67 lights on, 58-64 lights off. (Humidity did get to 70 briefly two nights of the past week)

The grow for reference:

3rd Time's a Charm: 6 Plants, 96 Colas

Hey ya'll We've officially started our third grow, and boy did we make some upgrades..where to start? Container: We scrapped the plastic pots and went with some nice 5 gallon shorty fabric pots from 24/7 Medium: We've switched to Promix HP and added some 4-4-4 Dr. Earth and 1/2 cuft EWC from...

www.rollitup.org

I referenced the leaf deficiency chart and from what I saw, it appears to be either Boron or Manganese issues. I haven't heard much surrounding these deficiencies so I wanted to get some opinions from the community.



Any help or advice is appreciated! Thanks!

Youve got a lot of N but not too bad,after reading you add 444 and other nutes I expected to see crispy plants.Not bad considering what youve fed them.The boost can do weird things,all the other nutes supply plenty of P K so no need for that.
Another thing that causes blotching is ph but I dont think in this case.
I grow in promix with gaia 444 nothing else but ewc and have no problems.

And they say brown spots on edges of leaves and in between the veins could be over watering issue.

myke said:

Youve got a lot of N but not too bad,after reading you add 444 and other nutes I expected to see crispy plants.Not bad considering what youve fed them.The boost can do weird things,all the other nutes supply plenty of P K so no need for that.
Another thing that causes blotching is ph but I dont think in this case.
I grow in promix with gaia 444 nothing else but ewc and have no problems.

Click to expand...

Hey man! Thanks for the input!

The 4-4-4 was the original amendment in the soil. Haven't added any since then besides a tea 3 weeks before flower. The EC has never been out of control and I've been keeping an eye on it. Only hit 2.9 the past two weeks with the bloom + boost, figured they could use some extra pk and once or twice in veg with calmag and full strength bloom. Now that I see burning on the tips I'm going to water only for the next 3 waterings.

I thought pH could be an issue if my pen was going bad (which they do). But I haven't noticed abnormal drifts in pH when testing the water. Seems to be right on par with what it was reading when it was new/newer. I'll recalibrate the thing and see if it reads differently.

ZuuTeD614 said:

And they say brown spots on edges of leaves and in between the veins could be over watering issue.

Click to expand...

Hey dude, thanks for the reply!
I find that odd in this scenario, I wouldn't consider my waterings overwatering. The plant in question takes 6L or 3gal each watering (5gal pots), at which point it starts to runoff (perfect, right?). They go 1 day in between watering/feeds, so generally 3-4 waters per week. (Feed-skip-water-skip-feed-skip-water...) and are pretty damn dry at the end of the dry cycle.

Lagged said:

Hey man! Thanks for the input!

The 4-4-4 was the original amendment in the soil. Haven't added any since then besides a tea 3 weeks before flower. The EC has never been out of control and I've been keeping an eye on it. Only hit 2.9 the past two weeks with the bloom + boost, figured they could use some extra pk and once or twice in veg with calmag and full strength bloom. Now that I see burning on the tips I'm going to water only for the next 3 waterings.

I thought pH could be an issue if my pen was going bad (which they do). But I haven't noticed abnormal drifts in pH when testing the water. Seems to be right on par with what it was reading when it was new/newer. I'll recalibrate the thing and see if it reads differently.


Hey dude, thanks for the reply!
I find that odd in this scenario, I wouldn't consider my waterings overwatering. The plant in question takes 6L or 3gal each watering (5gal pots), at which point it starts to runoff (perfect, right?). They go 1 day in between watering/feeds, so generally 3-4 waters per week. (Feed-skip-water-skip-feed-skip-water...) and are pretty damn dry at the end of the dry cycle.

Click to expand...

I am using a 7 gallon potnwith FFOF and sometimes I xan barely handle two gallons. I normally use a half gallon let sit for a minute use another half gallon let sit and most the time I can use a second gallon sometimes.only half of the second gallon.

ZuuTeD614 said:

I am using a 7 gallon potnwith FFOF and sometimes I xan barely handle two gallons. I normally use a half gallon let sit for a minute use another half gallon let sit and most the time I can use a second gallon sometimes.only half of the second gallon.

Click to expand...

Interesting..I would expect more water going into a 7gal than only 2 gallons. We use fabric pots and after putting 6L in this thing it is bone try by the end of the next day. Could be because of the high temps and high airflow that evaporates the overwatering quicker? Is that a thing? lol

Yup exactly what it is I see now. My Temps stay 81-83 with 35-45 percent RH on and off 70-72 with 45-53 percent RH

Wow the 2.9 ec feed,missed that in the first post may have been a lot much lol.continue to water and dont let it dry out otherwise all those nutes will turn to salt and cause more problems.A little runoff is probably a good thing since shes heavy on N and now P K.

myke said:

Wow the 2.9 ec feed,missed that in the first post may have been a lot much lol.continue to water and dont let it dry out otherwise all those nutes will turn to salt and cause more problems.A little runoff is probably a good thing since shes heavy on N and now P K.

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Hypothetically speaking...

lets say it dried out too much and it the nutrients did turn to salts - would that throw these kinds of symptoms? and yeah the 2.9 was uber aggressive but that's essentially what the Lotus feeding schedule calls for (2.8 ) Was this a bad move?

Lagged said:

Hypothetically speaking...

lets say it dried out too much and it the nutrients did turn to salts - would that throw these kinds of symptoms? and yeah the 2.9 was uber aggressive but that's essentially what the Lotus feeding schedule calls for (2.8 ) Was this a bad move?

Click to expand...

Another thing running fabric pots you will know if you have alot of salt build up because qtering pushes it to the outside so.if your fabric pots have white stains I'm guessing that would be salt build up correct? And that's from.letting your water dry to.much?

Lagged said:

Hypothetically speaking...

lets say it dried out too much and it the nutrients did turn to salts - would that throw these kinds of symptoms? and yeah the 2.9 was uber aggressive but that's essentially what the Lotus feeding schedule calls for (2.8 ) Was this a bad move?

Click to expand...

yea 2.9 is double what you would normally feed,as said boost will do weird things most if not all good growers dont use it.Marketing hype really.1/2 is always kinda the rule of what charts/bottles say.

Possibly a dumb question, but are you sure they aren't just scratching against the net/tent walls/other leaves?

Great looking plants btw!

Lagged said:

Hey man! Thanks for the input!

The 4-4-4 was the original amendment in the soil. Haven't added any since then besides a tea 3 weeks before flower. The EC has never been out of control and I've been keeping an eye on it. Only hit 2.9 the past two weeks with the bloom + boost, figured they could use some extra pk and once or twice in veg with calmag and full strength bloom. Now that I see burning on the tips I'm going to water only for the next 3 waterings.

I thought pH could be an issue if my pen was going bad (which they do). But I haven't noticed abnormal drifts in pH when testing the water. Seems to be right on par with what it was reading when it was new/newer. I'll recalibrate the thing and see if it reads differently.


Hey dude, thanks for the reply!
I find that odd in this scenario, I wouldn't consider my waterings overwatering. The plant in question takes 6L or 3gal each watering (5gal pots), at which point it starts to runoff (perfect, right?). They go 1 day in between watering/feeds, so generally 3-4 waters per week. (Feed-skip-water-skip-feed-skip-water...) and are pretty damn dry at the end of the dry cycle.

Click to expand...

in my honest opinion i am in promix in 7 gallon pots week 3 of flower and only give 1 gallon each plant every 4th day i have gone the route of over feeding and over watering so i am sticking to a minimum only feeding tiger bloom every other feeding and the other one water only i did a topdress with ewc so far they are healthy and happy at 58" tall too

exa

ZuuTeD614 said:

I am using a 7 gallon potnwith FFOF and sometimes I xan barely handle two gallons. I normally use a half gallon let sit for a minute use another half gallon let sit and most the time I can use a second gallon sometimes.only half of the second gallon.

Click to expand...

exactly i only give 4 gallons total for 3 plants in 7 gallon pots and by the 4th day they are ready again but only week 3 i expect them to handle 2 gallons each by week 5 or 6 these are 56 inch plants though

btw you will have a great harvest either way dont sweat it just get your dry and cure in order thats the mmmmmmmmmmmmmmmmmmmmmmmmmmmon
ey shot

See I am every other day about gallon n a half to two gallons. If I wait a 2nd day to water I can pour a half gallon in and have instant runoff through the lowest side of my pot. So I think it gets to dry waiting an extra day so I do every other day and seems good.

ZuuTeD614 said:

Another thing running fabric pots you will know if you have alot of salt build up because qtering pushes it to the outside so.if your fabric pots have white stains I'm guessing that would be salt build up correct? And that's from.letting your water dry to.much?

Click to expand...

This is a great deduction. I do have slight white stains on the outside. Perhaps I am in the beginning stages of lockout?

myke said:

yea 2.9 is double what you would normally feed,as said boost will do weird things most if not all good growers dont use it.Marketing hype really.1/2 is always kinda the rule of what charts/bottles say.

Click to expand...

I was always concerned about this marketing hype. I've seen people talk about half strength nutes due to over advertising. The plants seemed fine when I was doing bloom+calmag, started to see some signed of N tox so ditched the calmag around week 4-5. I wanted to really pump them up with some p/k. Guess I overdid it.

So when a manufacturer calls for 2.8, rule of thumb is to feed at 1.4?

weedstoner420 said:

Possibly a dumb question, but are you sure they aren't just scratching against the net/tent walls/other leaves?

Great looking plants btw!

Click to expand...

Not a dumb question at all! I did notice that most of these symptoms are occurring at the back of the grow, particularly near the walls. There is 1 fan leaf in the middle that is beginning to show signs but for the most part its the leaves in the back. I considered this, but the pattern on the leaves makes me believe it is something other than contact.

osowhom said:

exa

exactly i only give 4 gallons total for 3 plants in 7 gallon pots and by the 4th day they are ready again but only week 3 i expect them to handle 2 gallons each by week 5 or 6 these are 56 inch plants though

Click to expand...

It's really interesting to hear things like this. I will try backing the watering down, but I am pretty certain they will be bone dry the next day. We have high temps, high airflow, high porosity soil, and fabric pots. I really enjoy have 1 off day from pHing and watering these babes, but maybe I'll try to do less water more frequently (which essentially means watering every day) and see what happens.

No little bit of salt build up.is normal you should be able to get a damp rag and whip it off.

You got what 3-4 weeks left? so good idea to start reducing your EC soon.And ya 1.4 is a good EC for all your feeds.Good practice is to get some good runoff on the feed days and dont let the plant suck it back up.Plant looks good.

@weedstoner420 I think you win the gold metal. I went down there to check on your hypothesis and found this. This leave was recently tucked under and you can see the abrasions on the leaf where it was resting against the scrog.

Of course, there could be a lot at play here. I'm glad that everyone chimed in - I probably would have overfed these to the point of gluttony lol That and I am going to adjust my watering schedule.

Thanks for the help everyone!!!