Help Identify Ailment, and Give Opinion on Flowering

[PapaOscarTango]

Well, after a failed grow that started in the spring in organic soil, I started two seedlings in early July in coco. Bag seed, unknown variety, five shop flourescent lights, 87 watts total, using LST. They started off very healthy, then began showing the same or similar symptoms as what killed the soil-grown plants.

Pics of each plant follow. The first being the full plant, then a close-up of a trouble area. What do you think is the problem, and since this is a shed grow and it's mid-September with frost and cold temps only a couple of m onths away, is it too early to flower them? What's the youngest a plant can go into flower? I realize my yield will not be great, but it should be enough to get me through the winter.

#1


#1, close-up


#2


#2, close-up


Thanks in advance!

 

[azad]

Hi, Is this plant in coco or compost ?.it looks like a PH problem to me.
What type of nutrients are ya using chemical or organics ?
It looks old nuff to flower,,Most plants can be flowered once they reach 10-12" or around 3-4wks old.

 

[PapaOscarTango]

Hey, Azad. Thanks for the response.

Both plants are in coco. I'm using organic ferts (Pure Blend Pro, veggie blend + their CalMag) at the amounts given in the chart I picked up where I bought the PBP. I have a crappy PH mearing tool, can't afford a good one. Best I can tell PH is around 6. I use either rain water off my roof, or store-bought distilled water.

 

[bickeyb]

i would have to say definitely a ph problems causing nitrogen lock out

 

[azad]

Coco and organics is a tricky combo i belive.
I suggest lowering the PH a drop !

Your gonna need more light too..find a cheap 250w hps light and a cheap ph meter !! Them 2 things are a growers best friends.

I use chem ferts in my coco grows.most chem ferts now buffer to the right PH, so little or no ph down is required.

 

[PapaOscarTango]

What kind of chem ferts do you use, azad?

 

[SeaMaiden]

Hey, Azad. Thanks for the response.

Both plants are in coco. I'm using organic ferts (Pure Blend Pro, veggie blend + their CalMag) at the amounts given in the chart I picked up where I bought the PBP. I have a crappy PH mearing tool, can't afford a good one. Best I can tell PH is around 6. I use either rain water off my roof, or store-bought distilled water.

PBP are not only not organic, they qualify as chemical salt ferts.

IMO, you need to have a better idea of what's happening here. You haven't relayed how you're using those nutrients (ratios?). IMO, again, knowing pH when you're using chemical salt fertilizers such as PBP or GH is of extreme importance, moreso than knowing EC.

I will first suggest getting yourself that meter, you need to know what's actually happening, and you need to know what's happening in the root zone. For me, that means a slurry test of the media rather than a run-off test.

I will suggest second that you learn about vapor pressure deficit and how to affect those parameters.

IMO, your lights are fine assuming you're using the proper spectrum. 5,000K-6500K is the sweet spot (this is color temperature as measure relative to the sun and offers the user an idea of the blue-red wavelength ratio). You can go as high as about 7,000K, but I personally don't have experience with the reef bulbs that use spectrums in the 10,000K-20,000K range. I have read that 10,000K bulbs cause amazing vegetative growth, but haven't experimented with that yet.

We need to know how much you're feeding, when, how often, and at what pH at the very least to really offer you much help. If the RH in the growing area is low, it must be raised. I'm guessing it's low, <50%.

I can't think of anything else at the moment, would need more info from you to really say just what's going on, but at this point I will simply make my observations.

I see reddened petioles--indicates either P- or N-, or uptake/utilization issues (that darned pH thing again!).
I see necrotic leaf margins going from mid-plant to lowers, this may be indicative of a K+ (highly likely depending on the coir used).
I can see what almost appears to be interveinal chlorosis of lowers, which could cause many to suggest Mg-, but not me, I'm thinking we're still in K+ territory.
I see the little white specks, those are the least of your problems. They may be caused by bugs, I don't actually know for sure.
Leaves curled downward, is either an overage of nutrients, bordering on toxicity, or is related to poor VPD ratios. VPD is driven by temperature and relative humidity (VPD=vapor pressure deficit).

Once you learn what VPD is, you'll smack your forehead and say, "Oh!"

 

[azad]

What kind of chem ferts do you use, azad?

Helpfull info from SeaMaiden..respect !!

I keep it simple with Dyna grow nutes..

 

[PapaOscarTango]

Thanks for the reply, SeaMaiden. Good stuff!

Bought a pH meter today. I'm getting about a 6.3 - 6.7 reading. The dude at the gardening center said I'm supposed to be flushing them once every 3 weeks. I've never done that. So, I flushed them today with Clearex and water.

Yeah, I kind of thought my lights were sufficient, as long as I keep the plants trained so that they lay flat and keep them within a few inches of the lamps. I've got "reds" and "blues" that are in the spectrum range you mentioned. They've been on a 12 on - 5.5 off -1 on - 5.5 off shedule.

Interesting stuff about VPD. But it's a shed grow, there's not a lot I can do about VPD, if I'm understanding the concept correctly. The RH has been fluctuating from 35% to 100% over the last few months; the temps have ranged from 65 to low 90s during the lifetime of these plants.

Finally, I feed/water them every third day (every two if the soil is dry), and sometimes I just water them without nutes. I use 15ml/gallon of PBP Veggie formula with 15ml CalMag/gallon. I use rain water when I get a chance to collect some, otherwise I use distilled.

Thanks again, azad. I'll look into the Dyna nutes.

 

[vukman]

If the soil dries in two days, you might have a root bound issue as well........how big are the plants and what size of container are they in? You did say soil, right??

<add edit> I just looked at the pics again and realized that you can see the pot. Soil really shouldn't dry out that quick..it's a sign of time to change to larger pot/container....

Good Luck

 

[SeaMaiden]

Thanks for the reply, SeaMaiden. Good stuff!

Bought a pH meter today. I'm getting about a 6.3 - 6.7 reading. The dude at the gardening center said I'm supposed to be flushing them once every 3 weeks. I've never done that. So, I flushed them today with Clearex and water.

I disagree with that thought, and I'll suggest that instead of wasting time and money on flushing what you're trying to feed, that you simply offer a much lower concentration of feeding solution. If you do that, you won't need to mess around with flushing. Also, if you ensure the coir doesn't dry out completely, you won't need to mess around with flushing. Also, if you give simply water-only every few feeds, which is what I do, you won't need to mess with flushing.

Also, that reading for coir feeding is too high. Best pH range for feeding plants with coir as the media is 5.8-6.2, with occasional ranges outside, both below and above.

Yeah, I kind of thought my lights were sufficient, as long as I keep the plants trained so that they lay flat and keep them within a few inches of the lamps. I've got "reds" and "blues" that are in the spectrum range you mentioned. They've been on a 12 on - 5.5 off -1 on - 5.5 off shedule.

Interesting stuff about VPD. But it's a shed grow, there's not a lot I can do about VPD, if I'm understanding the concept correctly. The RH has been fluctuating from 35% to 100% over the last few months; the temps have ranged from 65 to low 90s during the lifetime of these plants.

Holy shit. That *is* a hell of a range you've got going there! Perhaps you can get the shed tightened up a bit for future grows.

Finally, I feed/water them every third day (every two if the soil is dry), and sometimes I just water them without nutes. I use 15ml/gallon of PBP Veggie formula with 15ml CalMag/gallon. I use rain water when I get a chance to collect some, otherwise I use distilled.

I would not use distilled myself, I don't see it as being very good for living organisms (these are my fish-eyes seeing). I would mix it with tap water.

With coco coir, you do NOT want to let the media dry out completely, especially since you're using chemical salt-based fertilizers. This can cause problems. If you can get a tray under the pot(s), then bottom water every time the tray is dry.

I never did well with the PBP nutrients, so I don't use them. My biggest problem was how they drive pH DOWN, really hard. I had to use my well water, and that locked out Ca. When I went to rain or RO/DI water, and then separated the Ca from the Mg (no more Cal-Mag in my basement!) I found that what plants really need is Ca and that Cal-Mag doesn't always give me such good control.

However, I don't recall seeing Ca-related issues in your pix.

It's also important to remember that coir tends to be high in K, so whatever you feed should be formulated with lower K values relative to N and P. K?

 

[PapaOscarTango]

Okay, pH measurement fluctuates. The 6.3-6.7 was taken when the soil was soaked from being flushed. On your advice, I've gone back to bottom watering. BTW, when I said "dry", I meant the surface was dry. The coco at 1 inch depth is always slightly moist when I water, never bone dry. I didn't detect you saying that was a possible cause of my problems, though.

Anyway, my latest measurement of the troubled plant is 6.0. Looking at some troubleshooting pictures around, it looks to this noob more like low potassium or lockout, due to the worsening of the brown edges and curling like all the pics I see of low potassium. I'll post a recent pic tomorrow, but it looks like pic #1 of low potassium in this thread, and sort of the phosphorous pics, too: https://www.icmag.com/ic/showthread.php?t=11688. I probably shouldn't ask if you concur with that until I've posted a new pic, but with my pH readings, and assuming this gauge is somewhere close to accurate, I should probably lower it a bit regardless. What's the best way to lower pH in coco?

 

[SeaMaiden]

PapaOscar, let me post up a graphic and a chart that I use regularly to help me figure out what's up. Then I'll remind you that deficiencies often look just like toxicities. Not all, but many do.

Lowering pH in coir is simply a matter of adjusting pH of the feed you're giving, and for me that was pretty easy AFTER I switched to using RO/DI (now also rainwater) from my well water. Not everyone needs deionization, but I felt that it would give me that much less crap in the water column to mess with my parameters. Once I did that I had no more problems with cultivation in coir. And so, that all goes to say that I don't think it really matters what you use, as long as you're mixing properly and not causing anything to precipitate out. I've used GH pH Down, AN pH Down, vinegar and citric acid. All work great if the water column is not alkaline (resistant to pH shift), all work terribly if it is.

Les Charts.

 

[PapaOscarTango]

Thanks, SeaMaiden. I really do appreciate you sticking with me.

I was thinking about what you said regarding rainwater. I don't have any, and it's not supposed to rain here for at least a week. But I do have a river a mile or two away. Wouldn't that work? Or would it have too many unknown nutrients or chemicals? Should I just go back to tap water?

Thanks for the charts. Any info I can get is great.

This may not help, but here's pics from today of my sickest plant. Oddly enough, the other seems to have gotten better.

 

[PapaOscarTango]

PapaOscar, let me post up a graphic and a chart that I use regularly to help me figure out what's up. Then I'll remind you that deficiencies often look just like toxicities. Not all, but many do.

Is there an explanation of that third chart, the Mineral Interrelationships? I'm not sure what it's telling me.

Lowering pH in coir is simply a matter of adjusting pH of the feed you're giving, and for me that was pretty easy AFTER I switched to using RO/DI (now also rainwater) from my well water.

What is RO/DI? I'm guessing RO is reverse osmosis, but DI has me stumped.

I've used GH pH Down, AN pH Down, vinegar and citric acid. All work great if the water column is not alkaline (resistant to pH shift), all work terribly if it is.

Les Charts.

Plain white vinegar? Do you need both vinegar and citric, or just one or the other?

 

[DrFever]

here is my opinion your growing in coco which is high in P to begin with your organic nutrients probably have a high P and K rating burns usually start at tip and work its way up the leaf in your pictures illustrated its sorta starts at tip but spots occur and side browning starts , which is a classic symptom of P toxic you need to flush weekly in coco
cause of the p blocking out other Key components
salt build ups in soil , as well , you not only got leaf issues you got root issues as well
your only fix is transplant let soil dry out back of on nutrients you need lots of calmag growing in coco i would suggest 1 ml per liter of organic food till plant recovers in new medium as well add calmag or epsom salt
if going back to coco you need weekly flushes hope this helps

 

[DrFever]

double post sorry

 

[SeaMaiden]

Is there an explanation of that third chart, the Mineral Interrelationships? I'm not sure what it's telling me.

It's meant to help show you which minerals react with each other, which ones need each other, and in which direction they're reactive. So you can see from the chart that Mg is reactive with Ca, but not Fe, for example. You'll see how P is reactive with almost everything else on the chart. That means that if it's out of balance, it can also lock out (block) uptake or utilization of other required minerals.

What is RO/DI? I'm guessing RO is reverse osmosis, but DI has me stumped.

Reverse osmosis with deionization.

Plain white vinegar? Do you need both vinegar and citric, or just one or the other?

I prefer a stronger acid than plain vinegar if I need to get high pH, alkaline water pushed down. You'll need a LOT if you use vinegar and your source water is alkaline. I've never used both but don't see why you can't at this time.