DIY soil results

[Olderfart]

Hello peeps. My first serious water only grow with my diy soil mix described here: (1) Olderfart's Dive Down the Living Soil Rabbit Hole | The Autoflower Network

Problem: leaf symptoms look like Calcium issue to me

Medium/grow method: Water only, DIY peat based soil mix

Feed: and supplements used: Water only, mostly surface creek water initially, but changing to melted snow as water supply replenished. pH ~6.3-6.5. Last couple days I have added ~150EC of Bud Explosion.

water source: Initially creek, changing slowly to more melted snow. Initial creek water was ~70-80EC, melted snow <30EC.

Strain/age: 4 strains, 51-58 days, details with pics

light used: DIY LED, PPFD varies among plants

Climate:~27 lights on, 22-23 lights off, 19.5/4.5 lights on/off, RH earlier ~50-60%, low 40% now to avoid mold, especially with the SSSC girl. Her colas are huge and an obvious mold risk.

Additional info: This is well into the grow with my DIY soil. My reading of these symptoms is that I have calcium lockout from low soil ph, excess N, or both. All plants have earlier shown initial Ca symptoms of scattered spots on leaves, and as the soil is depleted, symptoms are increasing. My main question here is not so much how to make the grow finish better (although suggestions about that would be welcome) as to figure out how to adjust the soil mix for the next grow if I stick with water only.

Here are some pics of the four plants. First up, SSSC Auto Ellephant, Day 58:

She has always shown hints of calcium issues, but the symptoms are now getting worse. She may be starting the fade, but it looks a bit early for that to my eye. I think she has at least a couple weeks to go.

Next up, Dinamed Auto CBD Kush, also Day 58:

She is very close to chop, maybe today, maybe tomorrow, so I expect that part of the picture here is the fade. The more advanced symptoms still look like calcium lockout to me. Again, initial spots on the leaves occurred on this strain as well. There are two plants in this pot, some of the foliage on the left are part of the younger plant.

Next up, Mephisto 24 Carat at 51 days:

Again, she may be starting to fade a bit, but I still suspect calcium mischief.

Finally, the Mephisto Fugue State girl:

This girl has been unhappy from the get go, showing canoeing consistently since very early. I backed off PPFD to ~400 a while ago, which seems to have made little or no difference. It is possible that the unhappiness has been nute balance all along, but I haven't much clue how that would work.

Absent contrary advice, my intent for the next round is to increase the dose of Dolomite lime and gypsum, and cut back on the high N additives.

Thanks for checking in. Any ideas @Mañ'O'Green, @Waira, @pop22? Does anyone think increasing the ph of my irrigation water would help this grow?
That's it for this post peeps, suggestions on how to make the soil better next time, or how to help the girls with their finish would be much appreciated.

 

[pop22]

Up the water PH, I advise against the dolomite, it's just not needed. If your are If you recycle that soil, add 20% more unamended potting soil. Or make a fresh mix without the epsom slats and garden lime, us just the dolomite, it has plenty of both Mg and Ca.

Running water only organics is containers under 10 gallons in size is a juggling act. Some strains just won't tolerate a strong mix. But I think your issue is PH related lockout. I'd PH the water to 7.0 for one feed then 6.8 from there on.

 

[Tom Bombadil]

Does anyone think increasing the ph of my irrigation water would help this grow?
That's it for this post peeps, suggestions on how to make the soil better next time, or how to help the girls with their finish would be much appreciated.

Changing the ph of the water will do little if anything to correct ph of the soil. And if the water is hard enough to hold its ph/change the ph of the soil mix when added to it, its also hard enough to add to the ph issue already showing. If it were my soil, it would go into storage bins with about 500 red worms and a bunch of banana peels and apple cores etc... (not knowing exactly what you've amended with as that would determine what I added)over the course of a few months then I would run a single plant in it again and adjust the amendments as necessary..
The issue here may be as simple as just not letting the mix age long enough before using it. Your plant kinda looks like one i ran with natures living soil a few years ago and the issue then was that the nls was too fresh/needed to age/wacked out ph. Living soil should regulate its own ph and if youre using water that affects your soil ph, you should stop using it because its too hard. If you're using living organic soil and having to ph your water, you're doing it wrong imo.

 

[Olderfart]

Up the water PH, I advise against the dolomite, it's just not needed. If your are If you recycle that soil, add 20% more unamended potting soil. Or make a fresh mix without the epsom slats and garden lime, us just the dolomite, it has plenty of both Mg and Ca.

Running water only organics is containers under 10 gallons in size is a juggling act. Some strains just won't tolerate a strong mix. But I think your issue is PH related lockout. I'd PH the water to 7.0 for one feed then 6.8 from there on.

They are on subirrigation, if I change the ph to 7.0, it will need to stay that way for a while unless I top water, which at this stage, I am not going to do. I may be able to pH to 7.0 for a couple days before bringing it back to 6.8.

These containers are 30 liters, so I figured that they should be big enough when I set this up.

Thanks for the reply @pop22, much appreciated.

 

[Olderfart]

Changing the ph of the water will do little if anything to correct ph of the soil. And if the water is hard enough to hold its ph/change the ph of the soil mix when added to it, its also hard enough to add to the ph issue already showing. If it were my soil, it would go into storage bins with about 500 red worms and a bunch of banana peels and apple cores etc... (not knowing exactly what you've amended with as that would determine what I added)over the course of a few months then I would run a single plant in it again and adjust the amendments as necessary..
The issue here may be as simple as just not letting the mix age long enough before using it. Your plant kinda looks like one i ran with natures living soil a few years ago and the issue then was that the nls was too fresh/needed to age/wacked out ph. Living soil should regulate its own ph and if youre using water that affects your soil ph, you should stop using it because its too hard. If you're using living organic soil and having to ph your water, you're doing it wrong imo.

Hi @Tom Bombadil, and thanks for getting back to me. The details on my soil are in the link at the beginning of the post. The soil is well aged, so I am sure that that is not the problem. The water is soft, now a combination of melted snow and creek water, total ~70EC to start.

I hear you loud and clear about the water pH not necessarily doing much for the soil. OTOH, at this point in the grow, I doubt that it could hurt, and it might help a little bit. Other than increasing the pH of the irrigation, there is bugger all else I can do to affect the soil ph issue this grow. If the problem is calcium, it is caused by low pH, high N, or both. If pH is the problem, I think it is too little lime in my mix which resulted too acid a mix for easy absorption of Ca. I used the Bugbee peat mix to start with, and I suspect that his mix may was tailored for different water with higher initial EC. Unfortunately, he does not go into that in the discussions I have found. At some point he did mention that his water was relatively high EC, but did not elaborate on what that might mean to using his mix with different water. I don't have a proper soil pH meter, but I may do a slurry test shortly once the second DMK is chopped. Once she is gone, I will not be concerned about digging up soil to see what I can find out.

At this point, I am not sure whether I will re-amend or start over for the next grow. I may learn more by starting fresh and making specific adjustments based on the results of this grow. If I start fresh, the current batch will be a nice addition to the compost pile, or I might use it in our deck planters for veggies this summer. The jury will be out for a bit.

Thanks again for chiming in, I appreciate you taking the time.

 

[Mañ'O'Green]

I think your problem is environmental. In your caution to keep RH low for mold control you have gone into the VPD red zone where the plant stops transpiring enough to bring in the needed elements.

 

[Tom Bombadil]

Looked at your initial mix and that seems pretty high in nitrogen (cow manure/chicken manure and earth worm castings). I think you're probably right about your assessment of the issue.. One thing you could do since you're pretty much running out of options, is make an ewc/molasses aact and add a bit of dolomite lime to it and top water it in. Could turn it around and allow you to finish out well if you care to bother..Looks like she could fatten up pretty good for another 2-3 weeks.
GL
Merry Christmas & Happy New Year!

 

[Olderfart]

Looked at your initial mix and that seems pretty high in nitrogen (cow manure/chicken manure and earth worm castings). I think you're probably right about your assessment of the issue.. One thing you could do since you're pretty much running out of options, is make an ewc/molasses aact and add a bit of dolomite lime to it and top water it in. Could turn it around and allow you to finish out well if you care to bother..Looks like she could fatten up pretty good for another 2-3 weeks.
GL
Merry Christmas & Happy New Year!

Thanks for having a look at the soil mix. Since these pots have been on water only, I suppose that top watering might be tolerable because there should not be a nute buildup to make mischief. I will give your idea some thought, that might be worth a try. I have lots of fresh EWC, so what you are suggesting might be doable. Do you have a link to how to do the aact you have in mind?

Thanks again for the help.

I think your problem is environmental. In your caution to keep RH low for mold control you have gone into the VPD red zone where the plant stops transpiring enough to bring in the needed elements.

Thanks for the feedback MOG, much appreciated. I will have another study of the vpd tables, I thought low 40% was still in bounds, but if not, I will try to bump it up a bit. RH in the low 40% is only for the last week or so, prior to that I kept it at ~50-60%.

 

[Olderfart]

Hey @Mañ'O'Green, I had another gander at the VPD info, and you are correct, I have been pushing the RH a bit. The RH I have been working with is just barely inside the red line according to vpdcalculator.com, so I got the humidifier back out and bumped it up to mid-high 40%.

I think the vpd issue probably made recent trends worse, but the issues I see started developing at higher RH a long time ago on all plants, although the M24C was notably less affected than the others. I may see if I can help things out through the finish by trying to get my pH up a bit. The girls will produce bud in spite of me as usual, good thing these plants are tough.

Thanks again for getting back to me, I appreciate your help. Your efforts here help make AFN the friendly and informative place that it is.

 

[Olderfart]

Hey @Tom Bombadil, I found everything I need re. AACT, so no need for a link. I am going to give your idea a try, I suspect that it may help out. I will also bump the pH of input water to 7 for a day or two before bringing it down a bit after that.

As I mentioned to MOG, it is a good thing these plants are tough, they usually manage to make some decent bud in spite of me. Thanks again for the help.