Looking at the plants i would definitely check that there isn't something nibbling at the roots.
The sulphur levels shouldn't be a problem.
VG
The sulphur levels shouldn't be a problem.
VG
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Sulfur toxicity and low P issues
- Thread starter Stoobeey
- Start date
Jist flipped out all well 3 of the 4" girls. Knocked off a good chunk of the soil. Only the cereal milk I couldn't really mess with. I did sit her on top of some of the commercial potting for now, but it has a shit load of roots. All the others meh. I could probably up pot the cereal but I want to see what my other 2 bins of soil come back on test see if I can use it before crushing the bag of baby bus . The 3 in 7 gals already they're just going to have to deal .. and I will probably ditch soil if when I make it thru flower
Didn't see anything last night on the ladies on the 4" pots. Not a ton of roots but has some nice long white roots though. Only 1 of them didn't really need soil swapped (it has a giant root ball. Wouldn't have been smart to try to remove the old Soil). No pest seen except for those stupid pot worms
Ca++
Well-known member
You feel the 40s is bad, but coco growers are seeing twice this in there runoff, which is what the coco has let go of. Much more will be tied up in the cec mechanism. I gave it 10 minutes but can't find a study, though have read one on actual levels. The sodium must be repressed by K, as it will be taken along with K. The cannabis plant can take on more Na than K, up to about 80% before it actually dies. With the K here being reasonable when viewed beside the Na, the effect of Na in the 40s, seems of little importance. What we are seeing is issues from low P if we just think about the main contenders. With a general lack of he small stuff, that the plants seem to be expressing as Zn mainly. Which could be more of a pH issue than anything else. Though as I say, I would look at this tm7 just to see that the Zn is abundant. Especially when cannabis has been seen it like it more than other plants generally get. It's ratio with Fe matters, so that too needs keeping up, to avoid Fe problems.
There seems a whole suite of problems. I would be coring the rootball out like an apple. Giving it a quick shower, or swim in the wavy bucket. Then re-potting. A full on 'run away' attitude, as it looks f.......
All the small ones I swapped into baby bus soil with a bunch of added perlite (waiting for another test on my other bins of mix to come back). No pest that I spotted replanting last night. One plant will actually need to go into its final 7 soon (I skip between 4" and final pot usually). The 3 I have in 7s I'm going to top dress and stick out. Not sure I. Want to deal with pulling washing and repotting . Well see. The kush cake is pretty much trash if you can't tell lol . That tm7 arrives today. Will top the guano and water in with the tm7. I'll take photos later but the 2 ok ones in 7s seemed to put on new growth yesterday actually.
pH . So do I use elemental sulfur to buffer it and not worry about added sulfur? I thought I read that gypsum won't buffer pH. I know my pH is a tiny bit over where it should be
Ca++
Well-known member
While some knowledge is transferable, I'm really a hydro grower. The low P would have me using phosphoric acid, which would have a slow but steady effect. I can't advise on this though, where you want to keep to organic methods.
I run compost quite often, but it's still a chemical grow. I'm just passing through here.. a voice in the crowd, not an organic mentor
I run compost quite often, but it's still a chemical grow. I'm just passing through here.. a voice in the crowd, not an organic mentor
Appreciate it jist looking for aggregate advice. I also work with hardcore Cali organic farmers who grow in ground and also dabble in organic outdoor dwc with tomato (and they're bomb), so I'm taking information from a few sources omg the way as I educate myself. I have a hp of cured bud so I'm ok for now
. I'm sure everyone will recover (except kush cake). And I have 5 seedings I'll have to sex. Plenty to do while I fix the soilSo my other soil test came back. pH is a tad higher , 6.8 vs 6.6(do i need to bother with elemental sulfur to lower it or root zone takes care of itself ?)
as for P and micros I have 3 to 4 weeks to cook in tm7 and some NP.
everything seems to be recovering now
6.8 ain’t terrible for soil growing imo. If you do want to lower the pH there are other ways besides sulfur that are organic compatible. I like citric acid in my water, it has a nice buffering capacity too. You can also do fermented things, like whey from milk.
Thanks yeah I would like to return this sulfur if I don't really need to use it 5 lb is an awful lot for the rare occasion I would really need to tinker with ph if at all this is the first time in 3 years since I started doing full Organics that I've even known what the actual pH of my soil.
I'm guessing the real Crux of my problem was the lack of micronutrients and phosphorus
When someone recommends using suffer to change the pH of soil, I'm skeptical because it's impractical. Your 6.8 pH is golden and will work perfectly. If you add organic matter each year to your growing beds you will be ok. Messing with the pH is impermanent because it doesn't stay the same over a year using chemicals. Plus chemicals are unreliable due to conditions. The best way to work alkaline or acidic soils is with the addition of good ole compost every year.
this is your issue, water only, your soil isn't balanced properly for water only, nor does it have an adequate nutrient density for that. ( CEC 5.3)
The biggest problem is too much mag and potassium in relation to calcium and the complete lack of Micronutrients.
with that mix you need to feed a good balanced fertilizer regime to get good results.
the testing service you used isn't providing all the info you need. I'd suggest you get the K2 test from spectrum or try logan. ask for all values in PPMs and don't provide any crop info. ask for a bulk density test, this gives the proper info on how much mineral to add based on how heavy or light your soil is, weed soil mixes are very light compared to field soil and therefor need less minerals added to achieve balance than a heavy field so would need. you want to add on the AA 8.2 test to get an accurate Calcium reading if you use logan labs, the Spectrum labs K2 test (slownickle's protocol) comes with it included.
this is your posted test plugged into my mineral balancing spreadsheet showing your Cation %'s
Calcium needs to be pushed to about 80- 85% to lower MG, K, and Na values lower.
P and micros need to be raised after you get the proper tests ran, Slow suggests aiming for a CEC of 10 to 12
I can try to help with a soil rec if you get a good test, Slownickle and folks like me who follow his mineral targets prefer Spectrum K2 or K3 tests, everyone else in weed seems to like Logan. you can do the bulk density at home by drying down the soil mix at 200 degrees in the oven until bone dry, then measure the volume in ml and weight in grams.
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St. Phatty
Active member
Once I was at the grow supply store, and talked with this guy who uses Sulfur in the same quantities as Phosphorus.
He was serious about it. He got started on that track and considered Sulfur to be a Primary nutrient, like NP and K.
Obviously that raises lots of questions but since he was growing pot he didn't want to elaborate too much.
He was serious about it. He got started on that track and considered Sulfur to be a Primary nutrient, like NP and K.
Obviously that raises lots of questions but since he was growing pot he didn't want to elaborate too much.
most folks agree that sulfur, Potassium (elemental), and elemental Phosphorus should be equal PPMs in a properly balanced soil for ag crops. I push S higher than P and K and find that it results in better aroma and flavor expression as well as better heath in my cannabis.
smell for yourself...
92 OG Kush
Chem D
Mac 1
Forum Cut
here's how you might adjust the base cation percentages to get in the range slow suggests for sandy and low CEC soils.
Tested values
from Slow's thread:
"If the soil is very sandy and has a low CEC, 85% Ca will be too much Ca. The number will be closer to 80-82% Ca, needing more K and more Mg. The Mg will make the sand drain less and hold both more water and build up more fertilizers. This would call for a 10-12% Mg and 6 to 8% K. This CEC would probably range from say 4 to 12 meq.."
by raising only the calcium from 731 ppms to 1325 ppms you can get into the range that Slow talks about above.
It is important to use a Calcium source that doesn't bring along added Mg like ag lime or oyster shells as Mg levels are already in excess. a better chioce might be Aragonite, Gypsum, or Wollastonite. in this case where sulfur is already high gypsum might not be the best choice as it bring almost as much sulfur as it does calcium. Aragonite is cheap and easy to get for about $15 for 50# at an organic feed supply, it's added to chicken feed.
Tested values
from Slow's thread:
"If the soil is very sandy and has a low CEC, 85% Ca will be too much Ca. The number will be closer to 80-82% Ca, needing more K and more Mg. The Mg will make the sand drain less and hold both more water and build up more fertilizers. This would call for a 10-12% Mg and 6 to 8% K. This CEC would probably range from say 4 to 12 meq.."
by raising only the calcium from 731 ppms to 1325 ppms you can get into the range that Slow talks about above.
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Thanks, I'll look into these more precise rest and adjustments later on. I'm just growing for me anyways (I'll be returning the sulfur figured that was a pointless purchase).
I already folded into my other base tm7 and the last of the fish bone meal I had left which wasn't much and seabird guano. I've got 3 to 4 weeks before anything needs up potting anyway. My other plants are recovering in that first soil test.
The 3 in 7s have all begin growing again and recovering since I sort of "flushed" then topped dressed in guano. Tm7, and ewc. Watered in with a tea with same stuff and some kelp meal 2 nights ago.
It's pretty wild seeing the plants that are near death and yellowing pushing out green growth already. In 3 weeks or so I may send off to try Logan next to see where that round of soil is after amending.
I had thrips too apparently, but already dropped nematodes, spinosad soap, and just got the pred mites today (cucumeris ones). Getting that shit knocked out fast
I already folded into my other base tm7 and the last of the fish bone meal I had left which wasn't much and seabird guano. I've got 3 to 4 weeks before anything needs up potting anyway. My other plants are recovering in that first soil test.
The 3 in 7s have all begin growing again and recovering since I sort of "flushed" then topped dressed in guano. Tm7, and ewc. Watered in with a tea with same stuff and some kelp meal 2 nights ago.
It's pretty wild seeing the plants that are near death and yellowing pushing out green growth already. In 3 weeks or so I may send off to try Logan next to see where that round of soil is after amending.
I had thrips too apparently, but already dropped nematodes, spinosad soap, and just got the pred mites today (cucumeris ones). Getting that shit knocked out fast
Ok so I need to pop new filters into my 5 stage . I had removed the ro filter recently (250ppm and 6.6ph is what comes out with no ro filter installed)
Should I be considering putting it back in? I've read so much back and forth o nthis (plus world health mentions RO is bad for drinking ). I have the membrane but was going to skip it when I put new filters in this weekend. I like the fact there's way less waste wo membrane too
Should I be considering putting it back in? I've read so much back and forth o nthis (plus world health mentions RO is bad for drinking ). I have the membrane but was going to skip it when I put new filters in this weekend. I like the fact there's way less waste wo membrane too
That's right before my last harvest. The gsc on the left and chem d variant in back are
. Smell amazing . They just hit 2 weeks in cure tooThese were the 3 super fucked up plants from when I first posted. As you can see all chugging along and into recovery. They've all greened back up and new growth is looking good!
Those are coming back pretty nicely.
