week 4 flower- boost nutes or ride it out?

I chose not to post in "problems" because I guess its not really a problem(or is it?). Week 4 of flower and I'm seeing some mobile deficiencies (nitrogen?) and senescence already. Not usually concerned about this but the lowers are kind of looking a bit droopy. So the question is should I boost the nutes a little bit or simply ride it out to the finish? Are we looking at a natural fade or am I forcing it a bit early? Pics taken at lights on. In reality the healthy leaves are pretty dark green still. Also cant see it but they are also starting to show some senescence at the top flowers as well (purple).

Edit: This started pretty early on in week 4. About 4 days ago.
Edit 2: the only other smaller plat in the tent just showed a tiny bit of purple this morning. No yellowing.

Temps 77f
EC 1.3
RH 60%
PPFD 800

How many times do you flood/feed every day? Looks like they're asking for more feedings. What are they being fed?

pH 6.0-6.5?

Cheers!

Wastei said:

How many times do you flood/feed every day? Looks like they're asking for more feedings. What are they being fed?

pH 6.0-6.5?

Cheers!

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Hydro rockwool

Twice a day at half strength. Dyna-gro bloom, pro-tekt, and Mag-pro. PH around 6. EC 1.3.

phosphorus ?

Her sister seems perfectly healthy.

Yup, pretty typical phosphorus deficiency.
There is some cupping and praying also, might be slight Mg deficiency aswell.
Both pretty mild, but could use a bump.

Whatcha been feeding her?

pegboy said:

Hydro rockwool

Twice a day at half strength. Dyna-gro bloom, pro-tekt, and Mag-pro. PH around 6. EC 1.3.

phosphorus ?

Her sister seems perfectly healthy.

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It's more or less impossible for that to solely be down to phosphorous deficiency with heavy P in the feed and mix. Cannabis is not a heavy P crop.

My bet is either root related and/or pH related. Do you use any anti fungal agents or oxidizers? If it only affect one plants I say it's probably root related.

Cheers!

Wastei said:

It's more or less impossible for that to solely be down to phosphorous deficiency with heavy P in the feed and mix. Cannabis is not a heavy P crop.

My bet is either root related and/or pH related. Do you use any anti fungal agents or oxidizers? If it only affect one plants I say it's probably root related.

Cheers!

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I was thinking the same thing. Don't typically use anti-fungals but I did give them a serious flush this morning. Hopefully that helps.

First run in this new set up with larger RW cubes. I guess I have a little more tweaking to do.

Is it possible that wet feet could cause this? I'm at that awkward place where watering once a day is to little but twice a day is a bit much. Roots look pretty healthy though (the dark spots are where the a channels in the tray are air pruning.). I'm leaning toward nutrient build up/PH drop. We shall see what happens after this large flush.



And the healthy one:

Why would twice a day be too much?

coreywebster said:

Why would twice a day be too much?

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If the rockwool retains too much water constantly the roots get depleted of oxygen. I like a little more dry back than I'm currently getting with two waterings. A negative to ebb and flow and rockwool.....In my situation/set up anyway. Just like overwatered soil. These cubes hold a shit ton of water.

pegboy said:

Is it possible that wet feet could cause this? I'm at that awkward place where watering once a day is to little but twice a day is a bit much. Roots look pretty healthy though (the dark spots are where the a channels in the tray are air pruning.). I'm leaning toward nutrient build up/PH drop. We shall see what happens after this large flush.

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And the healthy one:

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Yes, too wet medium could lock P out.

When I grew in rock wool I fed at 5.5 and runoff would always be over 6 (PH). EC was always more than that as well, lowest EC I've ever fed was 1.6. Drybacks are nice to get the roots going but it looks like you have plenty, if you're at the border line where 1 watering almost isn't enough then I'd definitely be watering twice, rock wool at full saturation has enough o2.

pegboy said:

If the rockwool retains too much water constantly the roots get depleted of oxygen. I like a little more dry back than I'm currently getting with two waterings. A negative to ebb and flow and rockwool.....In my situation/set up anyway. Just like overwatered soil. These cubes hold a shit ton of water.

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Ah, so because they're already full of water they won't absorb new oxygen loaded water.

I was looking at it like nft in rockwool or dtw coco where I could water as many times as I wanted .

Makes sense now

So I gave them a good flushing and dropped the waterings to once a day. If they seem a little dry I just run and extra cycle in the evening when I get home from work. Not sure what fixed it (if it even is) but she seems to be doing better. A few more weeks shouldn't be a problem at all.

Hey I have some plants doing the same thing week 4 and it was due to a high pH and not enough fertilizer because I was only watering them once a day with no runoff. I would in the future feed a little more acidic like 5.6-5.8 because pH will drift upwards most of the time in between fertigations depending on what you're putting in the rootzone.

pegboy said:

Is it possible that wet feet could cause this? I'm at that awkward place where watering once a day is to little but twice a day is a bit much. Roots look pretty healthy though (the dark spots are where the a channels in the tray are air pruning.). I'm leaning toward nutrient build up/PH drop. We shall see what happens after this large flush.

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And the healthy one:

View attachment 5393260

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pH might be drifting but "wet feet" is definitely a possibility. I've had weird shit like that happen when I had plants that weren't drinking as much as other on a automatic drip feed system. I am pretty sure its high pH related though...