Phosphorous deficiency

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oldfogey420

Well-Known Member
Hey folks. Please excuse my ignorance, I am not new to growing, but I am new to organics. Last round I tried out Nature's Living Soil (NLS) and had a nice harvest. This round is going even better than the first, but one plant has a pretty bad phosphorous deficiency that I cant seem to get past. At half way through flower, I've lost all lower fan leaves and now the upper fans are starting to go. The buds are developing VERY slowly. Not even half the size of others in the room. Every plant has the same amount of NLS in the mix, but I understand different genetics can have vastly different needs for nutrients.

In a typical grow I would just up the ante on bloom nutes and call it a day. I dont have that luxury now that I'm trying out organic only. I tried top dressing with additional NLS which has done little to nothing. I followed that by further top dressing with some homemade worm compost, straight out of the worm bin. No change for the better. I'm losing this battle!!

Is there a product I can purchase to quickly give this girl some much needed P, but is also still 100% organic and won't hurt the microbes in my soil mix? I'm not setup to make a proper tea, ie no air pump, so any compost tea that I make will just be whatever leaches into the water, and will not be full of active microbes as it should be. I'm also not too keen on any foliar sprays since they are 4 weeks into flowering.

Fyi, I am not growing in soil, its NLS with coco and perlite, not peat or potting soil. Last grow did just fine with that mix. I do not add nutes, although I just remembered that I also added some FF Big Bloom that I had left over, as I've been trying to combat this deficiency. I use R.O. water, although i admit that the filters need a change. My ppms were around 15 with new filters and is now around 45. My ppms straight from the tap are well over 400. I hesitate to think it's the water, because the other 4 plants are very happy and healthy.

Any input would be appreciated.

Thanks!
 
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oldfogey420

Well-Known Member
I always end up with fungus gnats when I use peat based soils. That gets old, grow after grow. I haven't used peat in years, and haven't had gnats either. No pics atm, maybe later. Pot size is 7 gal.
 
L

loco41

Well-Known Member
oldfogey420 said:
I always end up with fungus gnats when I use peat based soils. That gets old, grow after grow. I haven't used peat in years, and haven't had gnats either. No pics atm, maybe later. Pot size is 7 gal.
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You could maybe grab some fish bone meal/crab shell meal which both have good amounts of P and topdress with one of those and some fresh compost/castings. Not sure if that'll become available fast enough to benefit this grow, but may be worth a shot. Also, maybe some fish hydrolysate would be something to try as well. I think Npetune's Harvest fish comes in with a 2-4-1 npk or something similar.

No expert here, but I think I have read that coco tends to affect calcium and magnesium more so than peat (sorry too ate up to remember clearly) which would in turn have synergistic/antagonistic effects on other nutrients like P. So maybe you are dealing with some sort of look out or imbalance between the three instead of an actual deficiency. There are a lot of smarter people than myself here and some cool graphs floating around that hopefully you can pull some info from.

Best of luck finishing up the grow though sir.
 
Rurumo

Rurumo

Well-Known Member
Phosphorus deficiency is extremely unlikely in any common organic mix. I would consider other causes for the symptoms you are experiencing, as loco said. I'm not familiar with Nature's Living Soil, is that a product? Sounds like you are dry amending coco, what percentage of the mix is compost/earthworm castings?
 
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oldfogey420

Well-Known Member
Here's some info from their website. I used the super soil technique last time and this time. Like I said, no problems last time around and only 1 plant effected this time around.Screenshot_20210426-133356_Samsung Internet.jpgScreenshot_20210426-133421_Samsung Internet.jpg
 
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oldfogey420

Well-Known Member
I'll post a pic later. Shes looking bad enough that I may put her in a separate tent so the others can be less crowded.
 
O

oldfogey420

Well-Known Member
Pics at last. They were taken about a week ago. Things have only gotten worse for this girl in that most of the fan leaves are toast and now the largest of the bud leaves are beginning to be affected. It won't be long until the sugar leaves are affected.

IMG_1209.JPGIMG_1197.JPGIMG_1208.JPG
 
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oldfogey420

Well-Known Member
And here are some pics of all the girls, for reference. 4ft tent, 600w hps (the orange glow) in the middle and 100w quantum in each corner. Why not 1000w hps you ask...? Heat. Heat. And heat.

IMG_1205.JPGIMG_1207.JPGIMG_1206.JPG
 
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oldfogey420

Well-Known Member
So I'm at a complete loss as to what to do next. I bought a 40g aquarium air pump and started a tea last night to make with the super soil base mix and added some ff big bud a tsp of recharge and 2 tbsp of molasses. Which is currently brewing...
 
Richard Drysift

Richard Drysift

Well-Known Member
Brewing up a tea might help but at this point you need soluble npk to get to work fast. Go with something like Neptune’s harvest liquid fish. I always try to keep some on hand in case they go south in mid bloom or late veg. A top dressing of ewc, fish bone, and kelp meal could also help get them over the finish line but it will take awhile to break down and become available to the root system.
For the next run consider adding a high N base layer in the bottom of your final size bloom pots. I prefer Charlie’s compost brand chicken manure but cow manure or any other slow release fertilizer will help. Just a handful or two; the roots will grow deeper and find it as it is needed. I also suggest pushing in a Jobes AP organic spike or two into each container which feeds for 8 weeks; perfect for bloom phase. You sorta have to put what’s needed in the soil before there are plants in it.
 
N

Northwood

Well-Known Member
oldfogey420 said:
Pics at last. They were taken about a week ago. Things have only gotten worse for this girl in that most of the fan leaves are toast and now the largest of the bud leaves are beginning to be affected. It won't be long until the sugar leaves are affected.

View attachment 4894279View attachment 4894280View attachment 4894281
Click to expand...
Looks like a classic potassium deficiency to me. I bet potassium ions wash out of coco pretty quickly. Or it could be an excess of calcium or uneven watering or pH is causing the potassium issue.
 
Sif1

Sif1

Well-Known Member
oldfogey420 said:
And here are some pics of all the girls, for reference. 4ft tent, 600w hps (the orange glow) in the middle and 100w quantum in each corner. Why not 1000w hps you ask...? Heat. Heat. And heat.

View attachment 4894287View attachment 4894288View attachment 4894289
Click to expand...
First thing you need to do is flush. I ph my flush water to 6 then measure the runoff, also measure your nutrient runoff. Then feed with seaweed, balance fish fert as above and a well balance nutrient. When flushing can also use some nice warm water, put that in and leave it for 15 minutes, helps dissolve salts. Then carry on with your flush until your runoff is the same as what you are putting in.
 
Southernontariogrower

Southernontariogrower

Well-Known Member
oldfogey420 said:
Hey folks. Please excuse my ignorance, I am not new to growing, but I am new to organics. Last round I tried out Nature's Living Soil (NLS) and had a nice harvest. This round is going even better than the first, but one plant has a pretty bad phosphorous deficiency that I cant seem to get past. At half way through flower, I've lost all lower fan leaves and now the upper fans are starting to go. The buds are developing VERY slowly. Not even half the size of others in the room. Every plant has the same amount of NLS in the mix, but I understand different genetics can have vastly different needs for nutrients.

In a typical grow I would just up the ante on bloom nutes and call it a day. I dont have that luxury now that I'm trying out organic only. I tried top dressing with additional NLS which has done little to nothing. I followed that by further top dressing with some homemade worm compost, straight out of the worm bin. No change for the better. I'm losing this battle!!

Is there a product I can purchase to quickly give this girl some much needed P, but is also still 100% organic and won't hurt the microbes in my soil mix? I'm not setup to make a proper tea, ie no air pump, so any compost tea that I make will just be whatever leaches into the water, and will not be full of active microbes as it should be. I'm also not too keen on any foliar sprays since they are 4 weeks into flowering.

Fyi, I am not growing in soil, its NLS with coco and perlite, not peat or potting soil. Last grow did just fine with that mix. I do not add nutes, although I just remembered that I also added some FF Big Bloom that I had left over, as I've been trying to combat this deficiency. I use R.O. water, although i admit that the filters need a change. My ppms were around 15 with new filters and is now around 45. My ppms straight from the tap are well over 400. I hesitate to think it's the water, because the other 4 plants are very happy and healthy.

Any input would be appreciated.

Thanks!
Click to expand...
Piss on it. Fix her right up, might wanna do 10 to 1 water to pee.
 
G

GlueSniffer

Active Member
Liquid Bone Meal - not sure if 100% organic - I don't care much for certification labels. Herculean Harvest is 0-6-0
GH pH down is phosphoric acid based - not organic - can only use citric acid to lower pH in organics IIRC

Since Certified Organic Cannabis is not a thing in my closet, I don't see a point to jump through hoops trying to meet certification standards.
I use products certified for organic use when making my soil mix, but will also use products that aren't certified for organics if the plants seems to need something and I want to see quick results. I basically run a water only organic supersoil mix in 15 gallon pots, but willing to supplement with foliar feedings and/or fertigation. I previously used smaller pots (3-7gallon) and fertigation was needed.

I am going to try the pH down this run. This is new, never-used soil. My tap water is about 7.5 pH with 125ppm bicarbonate. I'll use pH down to get the tap water to about 6.0. My soil has pH of about 7.0. The soil has about 900 lbs per acre of P2O5, but less than 1 ppm of P falls into the soil/water solution as shown on the saturated paste test from Logan Labs.

I assume the soluble P would increase over time once I got plants in there and allowed life to do its thing. I am also going to inoculate with various products. I have Great White, VAM (from BioAg), Azos, and I recently added URB to the lineup - which I am excited to try. The Soil Doc recommended I try Spectrum PSB, Rootwise (BioPhos), or Microbe+ (not sure what product this is) if I wanted to try to increase the solubility of P using microbes. I considered these products, but the price is pretty high - so I decided I would try pH down. This might have a negative impact on the P solubilizing microbes in the soil - but I want to increase the P in the soil / water soultion. Soluble P is my goal. Microbes are nice, but I will lie, cheat, and steal to grow healthy plants without purple petioles.
 
Sif1

Sif1

Well-Known Member
If you know 100% its phosphorus deficiency just use Bat Guano. I would still flush first in case you have a fert lockup.
 
O

oldfogey420

Well-Known Member
More questions of course.

1. What would have built up in the soil to cause lockout? If I'm not using chem fertilizers then there should be no salt buildup, right?

2. If I flush, wont alot of the nutrients in the supersoil be flushed away leaving me with an even greater deficiency?

3. My other girls began to fade early. I guess that means I need to use more supersoil next time?

4. I still have 2-3 weeks left in flower. Would a small boost of chem ferts, like half strength, be detrimental? Will it kill thebmicroherd?

Thanks everyone for your help so far!
 
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