Diagnosis For Yellowing & Brown Spots & Maybe Slow Flowering

[MidgeSmith 1,671]

Yes, fair enough.  My intuition is that the CalMag will sort it, but I have backed it off a touch to relieve their stress while it does its magic.  Thanks for the help.

[MidgeSmith 1,671]

 

@Shumroom , @Tegridy Farms & @Oldbear

I have the report back and the water company tell me that in the last year the magnesium content has been as follows: Magnesium: Average 1.9mg/L (Min 1.3mg/L Max 2.6mg/L)
 

[MidgeSmith 1,671]

Their live online water report for the last year is:

Hardness level: Soft
Hardness Clark: 3.57 degrees
Hardness French: 5.11 degrees
Harness German: 2.86 degrees

 

Analysis    Analysis Units    No of Results    Minimum Result    Average Result    Maximum Result    No of results above PCV limit    UK/EU Limit

1,2-Dichloroethane     µg/l     24     <0.24     <0.26     <0.30     0     3
Aldrin     µg/l     23     <0.003     <0.003     <0.003     0     0.03
Aluminium     µg/l     77     <14     <14     44     0     200
Ammonium     mg/l     77     <0.029     <0.056     <0.064     0     0.5
Antimony     µg/l     8     <0.04     <0.17     <0.30     0     5
Arsenic     µg/l     8     <0.07     <0.15     0.24     0     10
Benzene     µg/l     24     <0.06     <0.08     <0.12     0     1
Benzo-3,4-Pyrene     µg/l     8     <0.001     <0.001     <0.001     0     0.01
Boron     mg/l     24     <0.011     <0.024     0.140     0     1
Bromate     µg/l     8     <0.53     <0.98     1.54     0     10
Cadmium     µg/l     8     <0.02     <0.07     <0.15     0     5
Chloride     mg/l     24     13.80     17.27     21.70     0     250
Chromium     µg/l     8     <0.4     <1.0     <2.1     0     50
Clostridium perfringens     No. / 100ml     77     0     0     0     0     0
Coliform Bacteria     No. / 100ml     204     0     0     0     0     0
Colony Count After 72 Hours at 22ºC     No. / 100ml     77     0     0     5     0     No abnormal change
Colour     mg/l Pt/Co     77     <0.70     <1.47     2.20     0     20
Conductivity     µS/cm at 20ºC     77     115     158     249     0     2500
Copper     mg/l     8     0.0017     0.0095     0.0390     0     2
Cyanide     µg/l     24     <4     <4     <4     0     50
Dieldrin     µg/l     24     <0.008     <0.008     <0.008     0     0.03
E. coli     No. / 100ml     204     0     0     0     0     0
Enterococci     No. / 100ml     8     0     0     0     0     0
Fluoride     mg/l     8     0.59     0.70     0.76     0     1.5
Free Chlorine     mg/l     204     0.11     0.47     0.72     0     No abnormal change
Heptachlor     µg/l     23     <0.003     <0.003     <0.003     0     0.03
Heptachlor epoxide     µg/l     23     0.000     0.000     0.000     0     0.03
Iron     µg/l     77     <8     <15     143     0     200
Lead     µg/l     8     <0.1     <0.1     <0.2     0     10
Manganese     µg/l     77     <0.7     <1.2     15.9     0     50
Mercury     µg/l     24     <0.034     <0.037     <0.097     0     1
Nickel     µg/l     8     <0.7     <1.0     1.1     0     20
Nitrate     mg/l     8     <2.80     <4.47     7.30     0     50
Nitrite     mg/l     8     <0.005     <0.008     <0.013     0     0.5
Nitrite - Nitrate Calculated     -     8     0.00     0.07     0.10     0     <1
Odour     Dilution Number     77     0     0     0     0     Acceptable to Customer and no abnormal change
PAH     µg/l     8     0.00     0.00     0.00     0     0.1
Pesticides Other     µg/l     1201     <0.003     <0.009     0.027     0     0.1
pH     pH value     77     7.35     7.92     8.79     0     Min 6.5, Max 9.5
Selenium     µg/l     8     <0.07     <0.29     <0.65     0     10
Sodium     mg/l     8     10.9     11.8     13.7     0     200
Sulphate     mg/l     24     19     29     38     0     250
Taste     Dilution Number     77     0     0     0     0     Acceptable to Customer and no abnormal change
Tetrachloroethene and Trichloroethene     µg/l     8     0.00     0.00     0.00     0     10
Tetrachloromethane     µg/l     8     <0.19     <0.20     <0.20     0     3
Total Organic Carbon     mg/l     24     <0.8     <1.0     1.2     0     No abnormal change
Total Pesticides     µg/l     24     0.000     0.000     0.006     0     0.5
Total Trihalomethanes     µg/l     8     18.91     25.34     34.11     0     100
Turbidity     NTU     77     <0.12     <0.19     0.53     0     4

 

[Shumroom 23,472]

@Oldbear?

What do you reckon for correction? 

 

Ratio ≈ 18:1

 

Atb 

 

 

[Oldbear 9,729]

3 hours ago, Shumroom said:

@Oldbear?

What do you reckon for correction? 

 

Ratio ≈ 18:1

 

Atb 

 

 

Depends on ppm, if it is very low on both I'd use a feed to adjust. If its high on one side then I'd amend with canna mono as it's clean and liquid is a more accurate measure 

[MidgeSmith 1,671]

Just now, Oldbear said:

Depends on ppm, if it is very low on both I'd use a feed to adjust. If its high on one side then I'd amend with canna mono as it's clean and liquid is a more accurate measure 

Thanks for getting back to us and sharing yon thoughts.

Given your comment about PPM, do you agree of the hypothesis floated by latigid aikon - that since the water only had an EC of 0.1 before Calmag and nutes, that essentially the ratio became less relevant and I might as well just use CalMag at the manufacturers recommended rate to bring the EC up to 0.4 before adding nutes? That's 3ml/L in my case.

Sounds like there's some agreement there. Does that tally or am I reading you wrong?

Edited March 25, 2022 by MidgeSmith
clarity and detail

[Oldbear 9,729]

6 hours ago, MidgeSmith said:

that since the water only had an EC of 0.1 before Calmag and nutes, that essentially the ratio became less relevant and I might as well just use CalMag

I never said that, in fact I'd avoid calmag altogether. Ec in soil is pointless. If you're in coco then sw coco nutes or in dirt, sw dirt nutes should be fine without calmag. 

Edited March 26, 2022 by Oldbear
Spelling

[Shumroom 23,472]

Hiya @MidgeSmith,

I've just been rereading this thread and noticed you didn't answer my first post/question when,

I asked about root temperature and I suggested that they looked hungry

 

 

Then the idea of Ca Mg levels took over, 

perhaps because you already suspected this,

I'm not convinced that is the main problem. 

 

 

So I'll ask again about actual root temperature and the min/max RH??? 

 

I think that it's more likely to be environmental rather than your water. 

 

Also noticed about the mixture of compost types,

so I'd ask what pot size they are in? 

 

 

This is why we recommend that people run a grow diary, 

so that if there are any issues that crop up, 

all of the details are available(if included at the time)

 

 

Ps. it's sometimes worthwhile checking out grow diaries/profiles when taking advice  

 

Post count is no indication of the grower skill

 

If you click on someone's avatar image you can get to see the different types of content that they have posted. 

 

 

 

Atb 

 

 

[MidgeSmith 1,671]

12 hours ago, Shumroom said:

Hiya @MidgeSmith,

I've just been rereading this thread and noticed you didn't answer my first post/question when,

I asked about root temperature and I suggested that they looked hungry

 

 

Then the idea of Ca Mg levels took over, 

perhaps because you already suspected this,

I'm not convinced that is the main problem. 

 

 

So I'll ask again about actual root temperature and the min/max RH??? 

 

I think that it's more likely to be environmental rather than your water. 

 

Also noticed about the mixture of compost types,

so I'd ask what pot size they are in? 

 

 

This is why we recommend that people run a grow diary, 

so that if there are any issues that crop up, 

all of the details are available(if included at the time)

 

 

Ps. it's sometimes worthwhile checking out grow diaries/profiles when taking advice  

 

Post count is no indication of the grower skill

 

If you click on someone's avatar image you can get to see the different types of content that they have posted. 

 

 

 

Atb 

 

 

@Shumroom sorry if some bits got missed, there's a lot to take in and I have to work out what some of the replies mean.  Some replies are a little esoteric to someone like me with only a few grows under their belt, so I end up flitting to other pages to try to work out what they mean without appearing too thick ;). It can take enough cycles that bits get missed.  Also I am a bit scatterbrained, have a lot of tics and worry that the slower growing plant will end up with a very small yield.  I need the produce of this grow to last me until Autumn ideally.  So apologies for my variable levels of attention and understanding

Root temperature is a steady 24C, maintained with a heatmat and sensor which is buried about 10cm down in a pot that is #35cm tall. I'd read that it was the right temperature for them to be.  This is my first grow with a sensor controlled heatmat on throughout the grow.

 

The pots are 12.5L Airpots. It is the first time I have used them.  I like them a lot.

 

The RH has varied throughout the grow as I am keeping it as steady as I can at the levels recommended by the VPD chart to go with the temperatures that I am maintaining as best I can.  So, currently the RH is typically 50%-60% most of the time in the lower half during the daytime 20 hours and upper half during the 4 hours night. The temperature is currently typically 25.5C during the day and 18C at night. (During seedling - vegetative I tried to maintain around 75% and have moved down progressively to try to mitigate the chances of mould and very slow transpiration).

I haven't posted grow diaries while in progress because to be honest, I get paranoid about posting too much about a grow while it is in progress.  I know that doesn't strictly make sense when I have posted images when asking questions, but there you go.  I got stung 25 years ago and try to keep my risks balanced. I posted one on growdiaries.com for the sweet-tooth grow I did, once it was finished and I'd made sure to keep the photos abstracted enough.  I do check other people's grow diaries on that site from time to time, I haven't here, apart from when the images are in the latest posts shown in the sidebar.  I am not sure how aware I was of them on this site, but I see them now in the forum categories.

Sorry if there was confusion Oldbear.  All I was saying is you mentioned PPM, which I presumed related to the EC of the water before and after Calmag.  I didn't know what you meant by "Depends on ppm, if it is very low on both I'd use a feed to adjust"  since the reading was taken to adjust for CalMag levels rather than feed and I thought you were somehow talking about adjusting for Magnesium deficiency with feed.  I didn't think Calmag should be required much in soil, particularly with supersoil mixed in, but the rust spots seem to have stabilised since I upped the dose, so it seemed to work.  However,  I have also upped the bloom nutes, so maybe it was that...

Edited March 26, 2022 by MidgeSmith
clarity and tone

[Shumroom 23,472]

Thanks for the detailed response @MidgeSmith

 

Nice one on the heat mats,

next time put the temp sensor down about ¾ of the way. 

 

 

18°C is too cold for lights off time though. 

 

Use either an oil rad or tube heaters to increase this to above 20°C or risk reduced yield and even worse, 

the possibility of hermaphrodism resulting in seeded buds

 

 

The increased Bloom probably helped I reckon. 

 

Atb 

 

 

[MidgeSmith 1,671]

Ok, noted thanks. I guess the root level temperature depth makes sense as it would be providing a reading of optimal soil temperature at the altitude where most of the root ball lies?  The yellowing and browning has definitely improved or stopped in the last few days thankfully, so cheers for the advice on the nutes.  Sad to think I was witholding nutrition on the basis of not wanting to overfeed and actually achieving the reverse, but hey!  There's always next time.

 

I am still a bit confused in the differing advice give regarding temperature and humidity.  It thought I must have gone a bit barmy while researching the grow, but I have gone back to some of the sources I think I used and they do seem to suggest cooler conditions than the experienced growers here, which seems odd.  I am not in ANY way doubting your advice or that of others here, but I am trying to reconcile them for the best understanding.

 

I think I got my temps from , Ed Rosenthal and Royal Queen Seeds 

 

They suggest no warmer than 25C / 26C during flowering to keep the buds from getting too airy, to keep flowers between 18C and 26C with the colder temperatures being at night, several degrees lower than during the day. Ed Rosenthal - whose book I had confiscated 25 years ago - suggests in a more recent volume that 26.5C is a good working maximum, raised from lower temperatures if you need to in order to help with relative humidity.

 

It is strange how much advice varies.  Here I've been told 28C is a far better temperature than 25C / 26C and night-time over 20C.  The required RH to cope with temperatures of 28C, according to the VPD chart is 55% - 65% which I would have thought put the grow into the danger zone for mould? I guess I must be wrong if more people here are growing at temps that high, than cooler temps?

 

I wonder if there is some kind of difference between UK and US advice on these things as most people definitely seem to be suggesting higher than 26C for flowering temps.  I can't think how to account for it, I would have assumed optimal growth would mean optimal flavour, maybe not optimal colour if lower night-time temps achieve a colour shift, but should only be applied in the very late stages to avoid lower yield?

 

It's an information minefield!

I am shocked to find that (presuming you are right about the nutrient levels being the reparatory factor) these autos need pretty much a full dose of nutes to thrive, even in a soil which is 2/3rds low nutrition to 1/3 high nutrition.  I know that they are listed as being a hungry strain, so I guess strains I have grown before were low hunger...  Such a high dynamic range for nutrition even between autos.  I hope I get better at dialling in per strain once I have my baselines sorted. 

 

I guess uneducated guesses aren't worth a great deal, so I will keep on listening and learning...

 

Thanks again for your continued help, advice and support. I hope my information reconciliation attempts don't read as contradiction to the advice given here.  Quite the opposite as I am following this new information, but trying to mentally marry it up with the other information on sites and blogs I trust in other ways.

 

Cheers!!

 

Midge

 

 

On 26/03/2022 at 6:50 AM, Shumroom said:

Hiya @MidgeSmith,

I've just been rereading this thread and noticed you didn't answer my first post/question when,

I asked about root temperature and I suggested that they looked hungry

 

 

Then the idea of Ca Mg levels took over, 

perhaps because you already suspected this,

I'm not convinced that is the main problem. 

 

 

So I'll ask again about actual root temperature and the min/max RH??? 

 

I think that it's more likely to be environmental rather than your water. 

 

Also noticed about the mixture of compost types,

so I'd ask what pot size they are in? 

 

 

This is why we recommend that people run a grow diary, 

so that if there are any issues that crop up, 

all of the details are available(if included at the time)

 

 

Ps. it's sometimes worthwhile checking out grow diaries/profiles when taking advice  

 

Post count is no indication of the grower skill

 

If you click on someone's avatar image you can get to see the different types of content that they have posted. 

 

 

 

Atb 

 

 

@Shumroom sorry if some bits got missed, there's a lot to take in and I have to work out what some of the replies mean.  Some replies are a little esoteric to someone with only a few grows under their belt. It can take enough cycles that bits get missed, so...

Root temperature is a steady 24C, maintained with a heatmat and sensor which is buried about 7cm down in a pot that is #35cm tall.

 

The pots are 12.5L Airpots.

 

The RH has varied throughout the grow as I am keeping it as steady as I can at the levels recommended by the VPD chart to go with the temperatures that I am maintaining as best I can.  so, currently the RH is typically 50%-60% most of the time in the lower half during the daytime 20 hours and upper half during the 4 hours night. The temperature is currently typically 25.5C during the day and 18C at night.

I haven't posted grow diaries while in progress because to be honest, I get paranoid about posting too much about a grow while it is in progress.  I know that doesn't strictly tally when I have posted images when asking questions, but there you go.  I will next time I guess. I posted one on growdiaries.com for the sweet-tooth grow I did, once it was finished.  I do check other people's grow diaries on that site from time to time, I haven't here, unless it was one of the latest posts shown in the sidebar.  I am not sure how aware I was of them on this site, but I see them now in the forum categories.

Sorry if there was confusion Oldbear.  All I was saying is you mentioned PPM, which I presumed related to the EC of the water before and after Calmag.  I had no idea what you meant by "Depends on ppm, if it is very low on both I'd use a feed to adjust"  since the reading was taken to adjust for calmag levels rather than feed.  I didn't think Calmag should be required much in soil, particularly with supersoil mixed in, but the rust spots seem to have stabilised since I upped the dose, so it seemed to work in one way.  I don't know.  I also upped the bloom nutes, so maybe it was that...

Edited March 27, 2022 by Dodgee
Remove exlink

[Shumroom 23,472]

Just a quick note to say that, 

External links are most likely to be removed by moderators

 

Atb 

I've got to go do the Mothers day thing just now, 

I'll reply properly later tonight 

 

[MidgeSmith 1,671]

Thanks mukka,

 

I forgot that was often the case.  Sorry admins/mods no nuisance intended!

 

Midge

 

 

Edited March 27, 2022 by MidgeSmith

[MidgeSmith 1,671]

On 24/03/2022 at 3:05 PM, inceywinceyspider said:

I think you should check out how much light they're getting as at 20hrs per day you might have the light power too high, look up a 'daily light integral chart' on google images.

It might not be causing the problems but may reduce stress if it is too much.

Hi @inceywinceyspider,

 

In case it is of any interest, I think your input was spot on here.  The two CMOG Autos are now trouble free.  They are still a mite yellow as I think I was underfeeding substantially and just maybe the calmag helped too.

But...The Sour Diesel Auto was continuing to get brown spots, noticeably on the higher leaves.  The tips started browning and curling upwards a bit too. I feel that the light was still too intense for them.  The CMOGAs were still lapping up as much light as I could throw at them and I don't want them to be undernourished, so I made a simple parasol for the SDA to reduce the light intensity.  It has brought it down by 1/4 to 1/3 which puts in in a much more temperate zone.

I think that with the other remedial action taken, this will be the salvation of the SDA and hopefully will prevent it from finishing way too early, heavily damaged and undernourished.



I thought you might be pleased that you had inspired a solution and provided - hopefully - the final part of the jigsaw

Edited March 28, 2022 by MidgeSmith

[inceywinceyspider 1,242]

 @MidgeSmith I am very interested, thank you very much for the detailed information. 

I'm really happy to have helped and I  hope it continues to go well.