can someone help me diagnose this issue?

[dustydundee]

This is some Chocolope on day 39 of veg. Using Ocean Forest soil with added perlite. Using GH trio with calmag. Temps around 70. Basically these leaves started to go brown about a week ago. A few weeks ago, I underwatered her for an extra day, she didnt like it, and some of the leaves discolored yellowish. Since then, she has been getting watered every 2 days. I've been light on the veg nutrients cause I'm using Ocean forest soil, and really right around now, from what I've read, is when that soil starts to run out of nutrients. I thought this was a phosphorous issue so about a week ago I gave her some of the foxfarm guano supplement, and yesterday I gave her the early flower mix of the GH trio, trying to boost her phosphates. Not sure I'm seeing any improvement, so wanting a fresh set of eyes on this. Is this phosphorous, or some other issue?

[JeffInCanada]

Hi dustydundee
I see that browning is happening at the lower and middle leaves...could be PH fluctuation, see below link. Have you been measuring the PH when you add water and nutrients? Could be the cause of other deficiency signs as well.

[Rqsnlautoproblems]

Kinda looks like potassium def, i'm a newbie though, hopefully someone with more knowledge will be along soon

[Farmbuck]

What is your PH ? As I see it, it looks like a mag deficiencies.

[PeterMatanzas]

When you’re watering be sure to mix up your pH, i.e. go with 6.5 one time, next time 6.3, then 6.5, then 6.2 ... I don’t mean exactly like that but make sure you aren’t always going with the same pH. Almost every time I have a nutrient issue it’s because of a pH problem - the nutrient is present in the soil but the plant can’t effectively use it because of pH

[PeterMatanzas]

Side issue: water when needed, not on a schedule like every 2 days.

[SoOrbudgal]

This watering and pot container is what we practice in the tutorials and all grow sites tell the same thing. If you ignore or try without knowledge mistakes will continue. No transplant, not knowing the size of the plant will get you into issues like this. Lack of proper water needs and over feeding. Hopefully they don't suck up the runoff and sit in water.

[dustydundee]

and what exact mistake am I making? not sure I find this comment very helpful.

[dustydundee]

Hi all, thanks for the replies...

as far as PH, I've been PHg each time to the low 6s. I shoot for 6.25 to 6.5. I ph it every time. I use the same meter for about another dozen plants.

As far as watering every 2 days, I've been weighing each pot and water when its light. When the plant was younger, it was going every 3-4 days, now based on her weight, she gets light every other day. She's in a 7 gallon container and I never let them sit in runoff. I originally had them in 3 gallon pots and transplanted them into 7 gallons a few weeks back cause they were drying out.

[homegrown]

agree with Jeff, next time you water, PH to 6.2 and run enough water thru it that you can test the Ph of the run-off. Im thinking a full blown flush might be in order.

[dustydundee]

good suggestions. I figure she will be due for a watering within the next day or two. I was thinking I was going maybe a little lite on my veg nutrients, but you think a full flush would be better first? (ok I had watering problems in my last grow, but this one is going much better. my other plants look good. if anything, i'm underwatering this time. I weighing these damn things every night and this guy seems to be light every 2 days or so) In any case, lets say within the next 24-48, she'll be dry. Last time I gave her some bloom supplements because I was thinking phosphate issues. Shall I give her a dose of the normal GH veg trio with calmag, or just do a full flush on her, followed by the GH veg after that dries???

[homegrown]

Nope, give it nothing but Ph 6.2 water. Give it lots till it runs out the bottom of the pail. dont test the first batch of run off, give it another good soak till run off and then test. If its not close to 6.2..then you'll need to think about flushing

[RetiredGuy]

I have also been struggling with what I believe is a phosphorus deficiency with one of my plants on my current grow. Your symptoms are similar. I had read that phosphorus is best absorbed by the plant above 6.2 pH. I have been feeding at about 6.5 pH, but my runoff is always about 6.2 which I think has contributed to the problem.

The plant with the deficiency is the one getting the most light, so I probably was too cautious and underfed it. I now understand that more light requires more nutes.

[dustydundee]

homegrown, I think I will follow that and do a good rinse with some PH water. I'm pretty sure I've been underfeeding it leading to this deficiency.... i guess my only concern/question then is, if this is the result of underfeeding, then by flushing it out now, wouldn't I be starving the plant more of some nutrients because then I'd have to wait several more days for it to dry back out before feeding it again? You'd think I'd be better off flushing it out, testing the runoff, and then feed at the same time after I flush on top of the flush? just askin....

[Catfish22]

It is a photo, correct? Either way it will be ok with no nutes for the couple days until it's time to water again.
Now you have clean medium to work with then just start back with your gh trio and cal mag at whatever week/stage your plant is at.
I don't do soil so I don't know if you have to recharge the calmag like you do in coco.

[dustydundee]

nope, not photos. still in veg.

[Catfish22]

It might take another week to start flowering.

[azorahai]

I'm pretty sure it's a calcium deficiency I'm seeing here (as well as some light burn at the tips of the top growth, but that's of little concern). Assuming you're feeding it enough calcium, then it's likely that the soil is too acidic. Hot soils shouldn't really be flushed afaik, but if this is really a problem with the pH then this might be necessary. Try to just water it and measure the run-off pH, if it's too low then you can proceed with the flush until the pH rises to an adequate level, and immediately feed it a pH'd solution of nutrients (including calmag), otherwise it'll just starve until the next watering.
That is, unless you're worried that it'll compact the soil too much, but if it has enough perlite mixed in it this shouldn't be a problem.

Edit: for future reference, adding some dolomite lime to your mix (before transplanting) is a good way of providing both calcium and magnesium to your plant, as well as maintaining an adequate pH level, specially if your substrate is acidic (such as peat moss).

[dustydundee]

azorahai you may be on to something with the PH flush and hot soil. They are in 7 gallon containers. I flushed through 2 gallons of ph'd water at about 6.2 to 6.4, my runoff kept measuring around 5.8 from start to finish, I was not seemingly making progress getting the runoff ph to move up at all. Is this what you would expect with hot soil? Just didn't seem like any more water was making much difference....2 gallons seems like a lot and it generated a good bit of runoff. At what point is too much water as far as flushing is concerned? 5 gallons? 10 gallons? any thoughts...

[azorahai]

I currently grow my plants in 11L pots with 50% peat moss, 50% perlite, and it took me flushing some amount over the volume of the pot (>11L) to get the pH to move from the low 5's to about 6-6.5, and for an even more thorough flush (for flushing out all nutrients, for example) it took about 2-3 times it's volume. If you think it can handle, you should probably flush it some more.
That being said, while 5.8 is a bit low for calcium uptake (it's supposedly best absorbed between 6.2-7 pH), it should still be absorbing some. You could also increase the amount of calmag you give it, and see if it helps.

[dustydundee]

thanks guys for both of those comments. it just seemed like a lot of water to me, but I guess I need to give her some more. its always good to get some real world feedback. appreciate it greatly.

[azorahai]

My pleasure. It took me a while to figure out that my medium can handle a lot of water, which it did recently when I switched from a terrible choice of nutrients (I didn't know any better when I bought them) to a custom salt-based solution that allowed me to significantly lower the ppm and still see an awesome development.
Let us know in a while if the problem subsided (or not).

[dustydundee]

azorahai, life got in the way and I couldn't post for a while, but the problem seems to have subsized with a good ph flush. at least twice the volume of the pot to get it to move. The plants are in early flower, I'm nursing them along, they still have some ph issues i'm struggling to balance out.

I guess my closing question on this is, what would cause the ph of the runoff to be so much lower then what I'm putting in? I've been trying to follow the basic guidelines, watering only when light, using the GH trio every other watering, I'm phing my water and nutes from 6.2 to 6.5, etc etc. If i'm putting nutes and water in at 6.5, why is the runoff at 5.5, what does that tell me I need to do different going forward? does that tell me that i'm putting in too many nutes? or not enough water? thanks for the input.

[azorahai]

From what I understand, GH nutes are very soluble and thus easily displaced when you water/feed (when watering, do it slowly so the soil hydrates without much run-off; when feeding, also do it slowly but try to wash out the remaining nutes from the soil with a 20-30% run-off), so you're probably not overfeeding it, but keep track of any burnt leaf tips as they indicate excess nutrients.
Your soil might actually be trending acidic and would likely have benefited from a pH buffer, such as dolomite lime. It doesn't take much (but please check with other soil growers for a reasonable amount to add), but it works best if you incorporate it before planting anything. Don't make the same mistake I made and topdress your plants with an absurd amount of lime to try to incorporate some of it, because I'm now fighting what appears to be a calcium toxicity during the flowering phase.
It's strange that it's trending acidic, as FoxFarm Ocean Forest soil is supposedly "adjusted at 6.3 to 6.8 pH", but I've never grown on soil so I don't know what can make it become acidic with time. Peat moss, for example, has a high amount of humic acids which helps it hydrate better among other things but also makes it trend acidic, which is what I was trying to remedy with my poorly thought out lime topdressing.

[dustydundee]

azorahai, little confused, you're saying I dont want a lot of runoff when watering, but get 20% runoff when feeding? I thought it was the other way around and I give it extra runoff when watering to wash out the old nutes?

[azorahai]

dustydundee Hydroponic nutrients, such as the General Hydroponics trio you're using, are easily dissolved and will leach out when watering. Whenever you feel like your plant needs more water but still has enough nutrients in the soil, you shouldn't wash those nutrients away, but rather only hydrate the medium so the remaining nutrients can be absorbed until the next feeding. Whenever you feel like your plant needs more nutrients, you should feed them until the solution runs off in order to remove any remaining salts (leftover nutrients) and introduce fresh nutrients in the correct proportion for the growing phase they are in.
If you water until run-off, you're hydrating the soil but also removing nutrients. In your case, since your soil already has some organic nutrients which aren't easily removed, your plants won't starve, but they will have less nutrients than intended until the next feeding.
If you feed without run-off, you're introducing new nutrients on top of any remaining nutrients already in the soil, which can easily compound and reach toxic concentrations (you'll notice its leaf tips will start turning brown if the concentration is too high, or if it's not too high overall but still has too much of any single nutrient, it can lock-out other nutrients, such as with the calcium toxicity in my case, which is locking out potassium and showing its symptoms all around).

From reading what others say, soil growers usually stick to mostly organic nutrients which are incorporated before planting with a periodic organic topdressing, and only occasionally introduce hydroponic nutrients to supplement what is already available in the medium. "Mr. Canucks Grow" on YouTube has a lot of videos on 100% organic grows. On the other hand, soilless growers usually stick to mostly inorganic nutrients (salt-based). In my case, I almost never water my plants, but instead feed them new nutrients whenever the medium is dry. Hydroponic nutrients are good for this, because they are easily displaced, so you don't need to flush them with water first and then feed, you can just feed until some amount runs off (in my case, I check the ppm and pH of the run-off until it registers an amount I'm satisfied with).

Next time, I'll give hydroponic (e.g. DWC) as well as a purely organic grow a try to see what works best. I like reading about plant nutrition and fine tuning things, so both soilless and hydroponic grows work better in this regard, but an organic soil grow has the advantage of being very low maintenance (or so I've been told), mostly only needing to be periodically watered and occasionally topdressed (e.g. to increase phosphorus during flowering).

[dustydundee]

azorahai thanks for the insight and explanation. that may be what has contributed to the issue. This current grow I've had a couple of plants have this issue, mostly my chocolopes. My jack herars are doing great, 1 month to harvest, and look almost perfect, with just one plant experiencing very minor ph issues. I've been watering and feeding both the same way, but my jacks are under more light then my chocos, so i'm thinking i have been overfeeding my chocos more then they can consume given the watts they were under, and not washing away the remaining nutes properly. the jacks didn't seem to mind, but the chocos didn't like it. i think this is my first and last time growing chocolope, not a very forgiving strain to grow.

I flushed a few plants in this ocean forest and i wasn't having much luck getting the ph much over 6. These are in 7 gallon pots, ph of the runoff started in the mid 5s, pushed 14 gallons through them only to wind up just a hair above 6. and then 4 - 6 days later when its time for the next watering, i check the runoff, and its back in the mid 5s. FML! I should be able to get something out of these chocos at the end, but not as much as I had hope for sure.... I think for my next grow, I'm gonna use FF happy frog. I understand its less hot then ocean forest, hopefully that means if this issue occurs again, I can adjust it easier?

So far on my shopping list I have dolomite lime for the next mix of soil with happy frog, along with some epsom salts. I've also been reading about this product:

https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

looks like lime with phup? I think I want to give that a try, ever try that?

[azorahai]

Yeah, my white widow is very unforgiving, it's had all sorts of issues and went through hell, but it's still outperforming my purple kush, which had practically no issues despite being treated exactly the same. At least I won't make the same mistakes next time — but there's always more room for new mistakes lol.
I honestly couldn't tell you if one soil mix is any better than the other in this regard. Try asking other soil growers here for tips. Still, a little bit of dolomite lime (~1/2 cup should do for a 7 gallon pot) should keep the pH from trending too acidic and will provide both calcium and magnesium to your plants. There's also calcitic lime, which is a lot more soluble and is probably what is in this ph up product, but it only provides calcium and won't last the entire grow. I've read people recommending you amend acidic mixes with both calcitic and dolomite lime, so by the time the calcitic lime is spent the dolomite lime is already available as a nutrient and as a pH buffer.

[dustydundee]

thanks for the help, i'll start another thread about the details of the mixes in soil and see where that goes. i think i'm going in the right direction, but as you said, there are always new mistakes to make around the corner.....