Dinafem Cheese XXL Auto - New Growth Yellow (and burnt tips)

[Life_On_Mars]

- pardon the lag mate, I got buried,...

Yup, as a general rule that's true,... My bad on not asking about light distance, that may have been a contributing factor but not the whole cause IMO,... That pic of the leaf shows P defc., not surprising because of the demand...
Micronutrients are mostly all immobile within the plant, Fe, Zn, Mn, B, Cu etc.,... Once established in tissues they can't be translocated to high demand growth anymore,... And in BioTabs I seem to see micronute defc. more often than usual. My choice for fixing that is earth Juice Microbalst, but overseas, it's not available. I like it because it's just micro's in rich conc., unlike kelp and most other products,...
I have no idea about how amino acids can affect solubility of CaCO3 (fairly poor solubility in water), in hard tap most of it isn't dissolved....
Same for AC water, I'm not exactly sure where that water has traveled in the system,... where it would pick up "heavy metals" is a mystery to me, and which ones? That it had 30ppm is something to consider, that's not insignificant, but what's dissolved in there is the question... Only ions will be measured by the TDS meter because they help conduct electricity...

That's a PK booster! ..above and beyond what the tabs provide at least,... Blending is fine...
Roots aren't the issue here in terms of what you said,... but constant soggy base is a worry for root rot, so watch out for that... Algae unless is bad isn't an issue either, just a nuisance..
pH is fine, so the CaCO3 load is being dealt with on that level at least...
Keep on the feeds, don't flush unless it's a shit-show for pH and massive run-off ppm!

No worries, thanks Waira. It took a couple of flushes to fix the low PH but they're back on track now. I re-fed them after the first flush with a very light orgatrex feed, but I saw some nute burn after that, and the soil didn't return to normal on the two worst affected plants so I flushed those again and didn't refeed. After that second flush then PH returned to normal, the bud growth returned, and the yellowing stopped. I can see that plant is hungry, but most of the trichs are cloudy now anyway, I think I'll be harvesting next week so I don't think I'll re-feed now. More info on the whole issue here -

https://www.autoflower.org/threads/dinafem-cheese-auto-xxl-day-43-frosty.78865/page-2#post-2310886

Some tasty bud pics here -

https://www.autoflower.org/threads/first-grow-ready-to-harvest.79170/

 

[Mañ'O'Green]

Well so much to consider here. I think that the roots sitting in non-aerated water under the first pot may be growing anaerobic microbes in the perlite. It is also like a flood and drain system in that it will have a water-line inside the soil where salts can and will build up. The wicking process carries the salts up to a certain level and stops without ever taking them back down. The flushing should alleviate that but the damage has been done and rinsing those salts out needs to continue. I would add Botanicare HydroGuard to out compete any anaerobic microbes. After this grow is completed I would be interested in seeing a cross section of the soil to see if the salts have been stratifying. Sometimes you can see evidence of this process on the outside of the fabric containers.

 

[Life_On_Mars]

Well so much to consider here. I think that the roots sitting in non-aerated water under the first pot may be growing anaerobic microbes in the perlite. It is also like a flood and drain system in that it will have a water-line inside the soil where salts can and will build up. The wicking process carries the salts up to a certain level and stops without ever taking them back down. The flushing should alleviate that but the damage has been done and rinsing those salts out needs to continue. I would add Botanicare HydroGuard to out compete any anaerobic microbes. After this grow is completed I would be interested in seeing a cross section of the soil to see if the salts have been stratifying. Sometimes you can see evidence of this process on the outside of the fabric containers.

Yes I certainly managed to over complicate things

That's interesting regarding the salt level - I'll take a look at the soil when I harvest. However - bear in mind that the water level never actually reaches soil level in this system. The bottom fabric pot has 5 inches of perlite, and the tray it's in has 4 inches of water. There's always an air gap between the main pot and the water surrounding the perlite pot below.

My water is certainly hard (350ppm) I can see the salt ring on the reservoir tray. Interesting that my soil PH got so low despite all the CaC03 in my water, but I was adding PH down (orthophosphoric acid) with each water... is that a 'salt' that could accumulate in soil if it's not being watered to run off? I had assumed not but perhaps I'm wrong. If I had to bet I'd guess it was the top feeds of orgatrex and PK 5-8 that acidified the soil though. I wasn't PHing those feeds, and the worst affected plants were the ones that got more feed (because I thought they were hungry), so it makes sense.

I've picked up a cheap RO system that I'll use for the next grow, mixed with my tap water. I do think I'm going to try the wicking system again for the next grow too - once the roots reached that air gap between the pot and the water then the growth seemed to really take off. I know it's my first grow so I'm not in the best position to judge, but I'm making comparisons to other grow diaries online of the same or similar strains. At 4 weeks mine looked like most others with equivalent lighting at 6 weeks, and it's certainly not my masterful growing skills as I'm a complete novice. The individual reservoir trays holds around 3 to 5 litres, and at peak growth I was refilling them twice a day. Soil was never soggy, always dry on top and moist just below the surface. I know it goes against the whole wet/dry cycle, but I think that consistent access to steady water combined with the 450w of QB being quite close to the canopy was really pushing them hard and spurring on growth during week 2 to week 5, at which point they got pushed too hard and started to yellow out from the lights.

They're out of the perlite swick pots now, because one pot was starting to go stagnant when I pulled it out to flush - it was only the water and the perlite at the very bottom of that pot that smelt. The roots were untouched thankfully. However, all the others were 100% fine (I just panicked and pulled them all to be safe). That specific pot's tray was having hot air blown onto it because of it's position in the tent (I'll fix that for the next run), plus that was the plant with the worst PH issue so it's growth had slowed right down and the water wasn't being consumed as quickly. I think that was the reason that one plant's water had begun to stagnate.

Regarding Hydroguard - thanks for the tip. Do you know how that is going to affect beneficial microbes in the soil, bearing in mind I use the biotabs line? I was previously wondering about just putting some H202 in the water solution every now and then, but had similar concerns regarding damage to microbial life. I had assumed that anything that's strong enough to kill that 'bad' bacteria in the water/perlite will also kill the good ones in the soil?

 

[Mañ'O'Green]

Yes I certainly managed to over complicate things

That's interesting regarding the salt level - I'll take a look at the soil when I harvest. However - bear in mind that the water level never actually reaches soil level in this system. The bottom fabric pot has 5 inches of perlite, and the tray it's in has 4 inches of water. There's always an air gap between the main pot and the water surrounding the perlite pot below.

My water is certainly hard (350ppm) I can see the salt ring on the reservoir tray. Interesting that my soil PH got so low despite all the CaC03 in my water, but I was adding PH down (orthophosphoric acid) with each water... is that a 'salt' that could accumulate in soil if it's not being watered to run off? I had assumed not but perhaps I'm wrong. If I had to bet I'd guess it was the top feeds of orgatrex and PK 5-8 that acidified the soil though. I wasn't PHing those feeds, and the worst affected plants were the ones that got more feed (because I thought they were hungry), so it makes sense.

I've picked up a cheap RO system that I'll use for the next grow, mixed with my tap water. I do think I'm going to try the wicking system again for the next grow too - once the roots reached that air gap between the pot and the water then the growth seemed to really take off. I know it's my first grow so I'm not in the best position to judge, but I'm making comparisons to other grow diaries online of the same or similar strains. At 4 weeks mine looked like most others with equivalent lighting at 6 weeks, and it's certainly not my masterful growing skills as I'm a complete novice. The individual reservoir trays holds around 3 to 5 litres, and at peak growth I was refilling them twice a day. Soil was never soggy, always dry on top and moist just below the surface. I know it goes against the whole wet/dry cycle, but I think that consistent access to steady water combined with the 450w of QB being quite close to the canopy was really pushing them hard and spurring on growth during week 2 to week 5, at which point they got pushed too hard and started to yellow out from the lights.

They're out of the perlite swick pots now, because one pot was starting to go stagnant when I pulled it out to flush - it was only the water and the perlite at the very bottom of that pot that smelt. The roots were untouched thankfully. However, all the others were 100% fine (I just panicked and pulled them all to be safe). That specific pot's tray was having hot air blown onto it because of it's position in the tent (I'll fix that for the next run), plus that was the plant with the worst PH issue so it's growth had slowed right down and the water wasn't being consumed as quickly. I think that was the reason that one plant's water had begun to stagnate.

Regarding Hydroguard - thanks for the tip. Do you know how that is going to affect beneficial microbes in the soil, bearing in mind I use the biotabs line? I was previously wondering about just putting some H202 in the water solution every now and then, but had similar concerns regarding damage to microbial life. I had assumed that anything that's strong enough to kill that 'bad' bacteria in the water/perlite will also kill the good ones in the soil?

The HydroGuard is safe.

STOP H2o2 is NOT safe. It will kill all organisms good and bad and thereby probably your plants as well since this is an organic type grow.

 

[Life_On_Mars]

Thank you @Mañ'O'Green and @Waira for your help - I'm nearly at the finish line now, but I have one more question I could use some help with -

One plant has been harvested and is drying as it seemed like it was pretty much done, and I needed to make room and lower RH in the tent as it was getting ridiculous. The other four are still going, LOTS of amber trichs on the sugar leaves but very few on the Calyxes. I think they are about a week max from being done, probably less. I didn't refeed them after the last flush as I was seeing nute burn issues on some of them. Three of the four seem fine with this, they appear to have enough feed to last them until harvest, they're just slowly yellowing out as you'd expect - however one of them is super hungry. It's very yellowed out and has cannibalised a fair few of it's fan leaves. I assumed it would be done by now so it wouldn't be an issue, but I think it's got a few more days to go.

Assuming it will be done within the next seven days - should I give this one a weak orgatrex feed now? Or is it too close to harvest? Will the feed even do anything in this short a time?

If I don't feed it and let it stay hungry till it's fully mature, will it start cannibalising the buds too, or stop them from maturing properly?! Or will the fan leaves just continue to die and then the buds will stop growing larger? (I can live with the second one, but the first one is obviously a concern).

Thanks for your help!

EDIT: Here is a pic of a bud from the plant in question, no LED, flash on -

 

[Mañ'O'Green]

I don't flush and I feed my normal schedule up to three days prior to harvest. I only quit then because the plants are done. You are close with that plant now. In fact I would say the harvest window has opened. Use a jeweler's loupe.

When the trichome are nearly all cloudy the harvest window opens:

Some clear mostly all cloudy = a cerebral, racy high.

All cloudy with 20% amber = a balance mind/body high

All Cloudy with 40% amber = sleepy time/couch lock buzz

All Cloudy with 50% plus amber = over ripe.

Tutorial - Is it time to Harvest

www.autoflower.org

 

[Life_On_Mars]

I don't flush and I feed my normal schedule up to three days prior to harvest. I only quit then because the plants are done. You are close with that plant now. In fact I would say the harvest window has opened. Use a jeweler's loupe.

When the trichome are nearly all cloudy the harvest window opens:

Some clear mostly all cloudy = a cerebral, racy high.

All cloudy with 20% amber = a balance mind/body high

All Cloudy with 40% amber = sleepy time/couch lock buzz

All Cloudy with 50% plus amber = over ripe.

Tutorial - Is it time to Harvest

www.autoflower.org

I've checked the trichs through a loupe and zoomed on my phone, and there are a bunch of amber heads on the sugar leaves but the calyxes are still mostly cloudy with a few clear, I'm not going for that early window, racy high - hence why I feel it needs a bit more time.

I wasn't intending on flushing either, just tapering down nutes. It was only due the PH issue that I had to do it, after the first flush I gave them a light feed and it burnt them, so after the second flush I didn't feed them.

I'm not at the correct trichome ratio yet on the actual buds - so do you think if I were to give it a light organic feed now, it won't negatively effect the final smoke? Or is there any point if it's so close to the end? I can see it's starving and the leaves are dying off, if I leave it another week, will the BUDS start dying off?

 

[Mañ'O'Green]

I've checked the trichs through a loupe and zoomed on my phone, and there are a bunch of amber heads on the sugar leaves but the calyxes are still mostly cloudy with a few clear, I'm not going for that early window, racy high - hence why I feel it needs a bit more time.

I wasn't intending on flushing either, just tapering down nutes. It was only due the PH issue that I had to do it, after the first flush I gave them a light feed and it burnt them, so after the second flush I didn't feed them.

I'm not at the correct trichome ratio yet on the actual buds - so do you think if I were to give it a light organic feed now, it won't negatively effect the final smoke? Or is there any point if it's so close to the end? I can see it's starving and the leaves are dying off, if I leave it another week, will the BUDS start dying off?

No the buds won't degrade. The plant stops sending carbohydrates to the roots in the last couple of weeks and sends it to the buds instead. This is why we add molasses in the last two weeks not to feed the plants but to feed the micro-organisms since the plant stopped doing it. This in turn sends more nutrients to the plants as the microbes stay in high gear.

 

[Waira]

:smoking:... flushing is about the only way to fix off-pH, if it's bad enough, and to deal with a possible overload of hard water minerals...
With organic feeds, there's no need to do that "flush" (no nutes, more of a cleanse") starvation routine... True nute demands are tapering off rapidly, but final production of terpenes and cannabinoids is still going on, so IMO keeping some light inputs is wise,... Not all nutes are mobile, and the fans and other tissues can't give up the other vital immobile types for support,...

My water is certainly hard (350ppm) I can see the salt ring on the reservoir tray. Interesting that my soil PH got so low despite all the CaC03 in my water, but I was adding PH down (orthophosphoric acid) with each water... is that a 'salt' that could accumulate in soil if it's not being watered to run off? I had assumed not but perhaps I'm wrong. If I had to bet I'd guess it was the top feeds of orgatrex and PK 5-8 that acidified the soil though. I wasn't PHing those feeds, and the worst affected plants were the ones that got more feed (because I thought they were hungry), so it makes sense.

well, the chemistry behind CaCO3 dissolving, pH buffering and all the other soil/nute interactions is pretty complex,... that can lead to some puzzling results! CaCO3 dissolves into Ca++ and CO3--, and it's the carbonate molecule that's involved with pH buffering; it quickly snags a free H+ to form bicarbonate, lowering acidity... More acidity dissolves it more and more, hence the buffering effect. That acid is strong, not weak like citric or acetic. It's not a salt per se, and the orthoP' will become available as a P source...
Feeds do tend to be acidic, but much more so with synthetic vs. organic... The soil herd, the roots both alter the pH as well as nutes are broken down, cycled, released and all the uptake chemistry going on in the root zone... A busy place that!
The buds look great! ... nevermind the fans on some, they are doing their job giving up the goods and so some may finished face-first and ragged, the buds are the prize as long as they look and smell great you're golden!

 

[Life_On_Mars]

Awesome, thanks guys.

I did give them another light feed last night. A very weak solution of orgatrex (3-2-6) and seaweed extract (for micronutes) simply because I can see the trichs aren't where I want them yet (SO close though) and I'm literally running out of fan leaves on that plant, even the high fans near the buds are wilting up and falling off, so I just wanted to make sure the plant had enough nutrition left to reach it's full potential. I know some growers like to literally let the plant 'die' in the pot, starving it of both food and water, and this can accelerate the curing process. I had considered just letting that happen with this one and seeing how it smoked, but trying that in this hot and humid weather just feels like opening the door and saying 'yes please fungus spores, feel free to come in and infest my plants today, I've weakened them just for you'.

I'm aware that the 'science' behind flushing (i.e excess 'salts' are 'flushed' from the actual plant over a few days/weeks) doesn't actually make a whole lot of sense, especially with organic feeds, but I wasn't sure if feeding this close to the end could still have a negative effect. Glad to hear it shouldn't be an issue.

Yes once you starting getting into the hardcore chemistry side of things it becomes really tricky to diagnose these issues accurately, at least without a professional soil analysis on each entire pot, week by week! It's gonna be RO water next grow, I'm thinking 70/30 RO and tap should give me a reasonably clean and PH stable water supply for my next group of girls. I'll still need to add a touch of PH down I expect, but it'll only need a VERY TINY amount because the water will be mostly RO.

@Waira do you think it would smart to amend the soil with dolomite lime next grow? It seems counter intuitive as I've got hard. 7.5-7.8 PH water, but I wonder if having some lime in the soil would have actually prevented this issue, plus my water will be providing calcium but not much magnesium, so the dolomite lime could provide some of that too?

I'm definitely glad I didn't chop them all over the weekend, as I've seen some serious calyx swelling in the last few days! The one that's I did harvest has been hanging (whole plant, untrimmed) for four days including very hot day times. Even with aircon in the shed it's been reaching 28/29 in the 'dry box'. Luckily stems are not snapping cleanly yet, even smaller ones, so I think even though it's been warm, the whole plant hang combined with the high humidity might save me me from the dreaded flash dry.