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Triple Super Phosphate Dose for Indoor Pots

Having a hard time finding any info on how much TSP to apply per cft of bagged soil, supersoil mix or whatever we want to call a mix based on peat etc. for indoor pots.

Any info or personal experience would be much appreciated.

Cheers!
 

Creeperpark

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Veteran
Having a hard time finding any info on how much TSP to apply per cft of bagged soil, supersoil mix or whatever we want to call a mix based on peat etc. for indoor pots.

Any info or personal experience would be much appreciated.

Cheers!
That depends on what's already in the substrate. What is the soil and what is it amended with?
 

Creeperpark

Well-known member
Mentor
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@Creeperpark

says on the bag its about 80% peatmoss and 20% clay. About 70L, ~2.5cft

minersls in mg/L
200 N
150 P2O5
250 K2O
@Creeperpark

says on the bag its about 80% peatmoss and 20% clay. About 70L, ~2.5cft

minersls in mg/L
200 N
150 P2O5
250 K2O
You may have enough phosphorus in the substrate now. You can take a single pot and add a tablespoon and see how it does but I wouldn't add it to all the soil.
What is the good ratio for cannabis? approximately 3:1:2
A recommended NPK ratio is approximately 3:1:2, with a slightly higher proportion of nitrogen. This formulation of cannabis nutrients ensures robust foliage development, strong stems, and overall plant health.
 
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Old Uncle Ben

Well-known member
Having a hard time finding any info on how much TSP to apply per cft of bagged soil, supersoil mix or whatever we want to call a mix based on peat etc. for indoor pots.

Any info or personal experience would be much appreciated.

Cheers!
Why do you feel you need such a high P food or supplement?

P is not a blossom activator or enhancer. Don't get sucked into the con man marketing. High P foods can work against you by inducing micros uptake and inducing N deficiencies if high enough. A 5-1-3 or 3-1-2 from start to finish is good.
 

PadawanWarrior

Well-known member
A 5-1-3 or 3-1-2 from start to finish is good.
I'd have to disagree with that, especially the 5-1-3 all the way through. I just looked at some of your grows and it reaffirmed to me that you're using too much N and not enough P. Take this plant for example. Clawing from too much N and the purple looks like P deficiency. Too much N also interferes with flowering and makes them take forever to finish.

ben.jpg
 

Old Uncle Ben

Well-known member
I'd have to disagree with that, especially the 5-1-3 all the way through. I just looked at some of your grows and it reaffirmed to me that you're using too much N and not enough P. Take this plant for example. Clawing from too much N and the purple looks like P deficiency. Too much N also interferes with flowering and makes them take forever to finish.

View attachment 18989452
You cherry picked a pure afghani indica, aka "Afghan Mix" from Kwik Seeds, a photo I recently posted, not what I've posted for 20 something years. Apples and oranges if you consider the typical mutts grown around here.

The purple leaves is typical afghani, late blossom leaf coloration. Can also be caused by cold.

Get to know phenotypes before shooting from the hip.
 
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PadawanWarrior

Well-known member
You cherry picked a pure afghani indica, aka "Afghan Mix" from Kwik Seeds, a photo I recently posted, not what I've posted for 20 something years. Apples and oranges if you consider the typical mutts grown around here.

The purple leaves is typical afghani, late blossom leaf coloration. Can also be caused by cold.

Get to know phenotypes before shooting from the hip.
Don't take it the wrong way. I just disagree about giving it 5-1-3 all the way from start to finish.
 

Old Uncle Ben

Well-known member
Don't take it the wrong way. I just disagree about giving it 5-1-3 all the way from start to finish.

Well it does support the unit, leaves, that produce buds. I'll admit a 5-1-3 is a bit heavy on the N. Same can be said about a 3-30-28 being too low on N for good leaf retention and health up until harvest.

I use a lot of Osmocote 15-9-12 and it produces well for not only cannabis but for other crops (tree seedlings, veggies, rose bushes, etc.) as newly planted and long time established i.e. tropical fruit trees. . It's "fair and balanced".

That leaf tip curl can be caused by many factors as it's moisture related. As long as the leaf is still healthy it is not an issue regarding photosynthesis. Where are you getting this stuff that it's N related? From some internet parrot who read it in some thread? Anyone ever forked up a control group to support their position? Of course not.

BTW, welcome to IC Mag. I too spent too much of my time throwing pearls before swine on Troll It Up. Like you and many here I got banned. Wear it as a badge of honor. :)

My 4 cola topping thread had over a million views last time I looked, and sadly all the original photos explaining my "method of madness" were long wiped cleaned by that shit head Potroast or one of his enabling Latrine Getters.

UB
 

PadawanWarrior

Well-known member
Well it does support the unit, leaves, that produce buds. I'll admit a 5-1-3 is a bit heavy on the N. Same can be said about a 3-30-28 being too low on N for good leaf retention and health up until harvest.

I use a lot of Osmocote 15-9-12 and it produces well for not only cannabis but for other crops (tree seedlings, veggies, rose bushes, etc.) as newly planted and long time established i.e. tropical fruit trees. . It's "fair and balanced".

That leaf tip curl can be caused by many factors as it's moisture related. As long as the leaf is still healthy it is not an issue regarding photosynthesis. Where are you getting this stuff that it's N related? From some internet parrot who read it in some thread? Anyone ever forked up a control group to support their position? Of course not.

BTW, welcome to IC Mag. I too spent too much of my time throwing pearls before swine on Troll It Up. Like you and many here I got banned. Wear it as a badge of honor. :)

My 4 cola topping thread had over a million views last time I looked, and sadly all the original photos explaining my "method of madness" were long wiped cleaned by that shit head Potroast or one of his enabling Latrine Getters.

UB
Right on. I thought that curl was from N toxicity. I didn't know other nutrients could cause that too. I still get that occasionally and figured it was too much N. I'm no pro. I've only been growing seriously for 6 years so I still have much to learn. Sorry if I came off rude or anything. I didn't mean to if I did.

And Ya that Potroast loser was a major A hole. That place has majorly went downhill in the last couple years. I like it here much better anyways. :)
 

Dequilo

Plant Abuser
ICMag Donor
Veteran
420club
@Old Uncle Ben so when I water my in ground plant in with dose of NPK 0-52-34

I am shooting myself in the foot? :( say it isn't so!

be safe and grow well

Dequilo
 
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That superphos is going to form dicalcium phosphate as soon as it hits the soil. So, the amount of free calcium in your soil determines your fate. Better to feed calphos and calphos dissolving microbes/acids. Stay away from pothead bottled products though. Some shitheads think aspergillium is a good citrate producer for organic weed crops. So much "cheesey" weed out there in the unregulated state-legal markets, reaking of bacillus-treated fungal infection. Organic means covered in fucking layers of microbes when it comes to weed crops.



That curl is a lack of B. The mauve color means excess Nitrate failing to be metabolized into aminos thanks to Mo deficit. Not sure how any of you internet voices come to the conclusions you do.

Did you bother reading the reschedule recommendations? Ic mag is mentioned, something like "these internet kids shouldn't be allowed to grow this crop, look at the weird stuff they believe, and the flawed plant chemistry it leads to. We need pharma weed legalized, not this icmag boof"
 
Maybe I should’ve specified my Calcium in that mix is 75% of CEC, thats why I want to up the P so I can feed more K.

The mix is used for flowering only.
 

Old Uncle Ben

Well-known member
and see I always thought Phosphorus (P) and potassium (K) are the two main nutrients that stimulate

root growth.

why I use it at planting :(

Dam Cornell

all the best and be well

Dequilo
Sure they're required. It's the amount that folks don't get.

Like all noobies, I too fell for the high P bloom foods "that produce bigger blossoms and fruit" many years ago. Since then I learned and realized thru practice that a plant doesn't need that much P and it can work against you. Won't get into to it but such concepts as nutrient antagonism come into play...and other issues. So, folks like Dyna-Gro (and others) have created what I consider "the perfect" NPK of 9-3-6 or a 3-1-2 ratio. I don't overthink this and also consider economics and maintenance, one reason why I use a lot of Osmocote 15-9-12 which provides a good NPK balance (and micros) for most plant materials including weed.

Here's a ditty I wrote 20 years ago on the issue. Probably needs tweeking by now as my focus has changed a bit since then.

The never ending abuse of Phosphorous to enhance flowering

A common mistake for growers when they reach the flowering stage is to start hitting the plants with a high P fert like a 10‑50‑10, continuing to use this blend exclusively, and when their plants start experiencing a deficit of N, Ca, Mg or micros as reflected by the dropping of lower leaves and chlorosis, they wonder why. Plants flower as a response to long nights (or chronological age if equatorial), not because of food blends high in P (or K). A ratio of 10‑30‑10 is WAY too high in P. The plant will only take what it needs and compete for other elements that may be more important at the time.

You may have heard that too much N can inhibit flowering. No question about it, exclusive use of a plant food that is rich in N such as blood meal, a 5‑1‑1 blend, or ammonium nitrate/sulfate may inhibit flowering especially if the phosphorous level is low, but most balanced blends have sufficient amount of P to do the job. The question is ‑ "how much P is enough to support a good flowering response and still retain my leaves?"

Manufacturers/horticulturists will give you element analysis and what effect the elements have on plant growth, but remember this does not necessarily mean you will get better yields. Using a high P fert exclusively during flowering can actually work against you due to impending leaf drop. It's an abundant amount of healthy leaves going into 12/12 and maintaining their health until harvest that produces a lot of bud, not high P, or low N foods.

I rotate fertilizer blends as the plant *requires* them, not because it is "the thing to do." For example, when your plants are going thru the stretch phase during early flowering, they may need more N, especially if you're getting some yellowing in the lower leaves. Give up the cannabis paradigms and give them what they need. You may want to return to a mild high P fert when the stretch ends, maintaining the foliage in a healthy state of growth until harvest for maximum yields. A 1‑3‑2 blend such as Peter's Pro Blossom Booster, 10‑30‑20, is a good choice because of several factors ‑ it is higher in nitrate N and Mg and has a good micro package. It is sold under the Jack's Classic label.

There are many foods I stock in my toolbox. Dyna-Gro is another excellent brand. I use a lot of their Foliage Pro - 9-3-6.

Stay away from cannabis specific foods. They market unsuspecting newbies who don’t yet have a handle on plant nutrition and soil chemistry.

Uncle Ben
 

Chunkypigs

passing the gas
Veteran
Having a hard time finding any info on how much TSP to apply per cft of bagged soil, supersoil mix or whatever we want to call a mix based on peat etc. for indoor pots.

Any info or personal experience would be much appreciated.

Cheers!
P and K should be equal and target K at 7% of the media's base saturation using a combo of M3 and AA 8.2 when testing the media when your Ca level is at 87% in a clay heavy soil.

it works like this...
be beds.png



Double OG chem 7.23.23.jpg



BE DOC  Levitate 9.28.23.JPG


BE pitty 9.28.23.JPG




Doc 17  9.26.23.JPG




Wt Truffle 10.19.23 copy.JPG



Zkittlez 10.7.23.JPG




DSC_0176.JPG
 
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Old Uncle Ben

Well-known member
1. That curl is a lack of B. The mauve color means excess Nitrate failing to be metabolized into aminos thanks to Mo deficit. Not sure how any of you internet voices come to the conclusions you do.
"Speaking of internet voices", no, not sure how you think the curl is caused by a B deficiency. It's a moisture stress issue. For starts blooming/fruiting plant material requires B albeit in VERY small amounts to support reproductive processes. I add it to my tropical fruit trees a month before flowering in the form of Solubor. Sometimes add to cannabis if my food doesn't contain B, but most do.

Solubor.jpg


Another GREAT indica from yesteryear with the typical purple anthocyanin pigments - Cannacopia Lapis Mtn. indica. (Keep kicking myself in the ass for not making seeds, ug.) What an incredible high.

Cannacopia Lapiz Mtn. indicaMarch7.jpg


Ditty I wrote many years ago published on a lot of cannabis forums FYI:

Plant Moisture Stress - symptoms and solutions (revised May 30, 2011)

Quite often I hear groans from folks having leaf problems: "Help, my leaves are cupping and the leaf edges are turning brown!" or, "My plant's leaf tips are curling down and turning black ....what's wrong?" Unless insect damage has occurred or the plant is suffering from a severe case of calcium deficiency, the plant is trying to tell you that it is water stressed. It's hard to tell exactly what the culprit is, and unfortunately the solution the grower chooses many times is not the right one. A miss‑diagnosis only serves to make matters worse by promoting further decline. I'll try to cover some of the more common causes that can induce these common symptoms and try to offer a few simple solutions. The ultimate and correct solution is in the hands of the grower.

1. Over‑fertilizing ‑ the most common cause of leaf cupping aka leaf margin rolling, leaf margin burn, leaf tip curl/burn and copper colored round spots is the overzealous use of too much plant food in relationship to factors such as plant vigor and rate of growth. The first unit of a plant to show moisture stress is the leaf at its margins and/or tips, reflected by margin rolling (cupping) or burning. A hard, crispy feel to the leaf frequently occurs as well, as opposed to a soft and cool feel of a happy leaf. When you have a high concentration of salts in solution (or in the root medium) compared to lower salinity levels found in the plant's tissue, water is actually drawn out of the plant across the root gradient in order to fix the PPM imbalance. IOW, this is a natural, osmotic response that serves to equalize salinity levels on both sides of the root's epidermal gradient. Back off on the amount and/or frequency of plant food. Too much plant food can also burn the roots, especially the sensitive root tips and hairs, which then creates another set of problems such as nutrient deficiencies. A note for the bio folks ‑ as soil dries, the concentration of the remaining salts rises further exacerbating the problem. Leech (flush) your pots once in a while to get rid of excess salts.

2. High Heat ‑ the plant is losing water via it's leaves faster than what can be replaced by the root system. The leaf responds by leaf margin cupping or rolling (up or down) in order to conserve moisture. A good example is reflected by the appearance of broad‑bladed turf grass on a hot summer day, high noon, with low soil moisture levels ‑ the leaf blade will roll in and the grass will take on a dull, greyish‑green appearance. Upon sunrise when moisture levels have returned to normal, the leaf blade will be flat. Lower the heat and concentrate on developing a large, robust root system by practicing sound plant culture. An efficient and effective root system will go a long way to prevent heat induced leaf dessication and leaf margin curling by supplying sufficient moisture for good plant health. One short episode of high heat is enough to permanently destroy leaf tissue and cause a general decline in the leaves affected, which often occurs to leaves found at the top of the plant located to close to HID lamps. The damaged leaf (usually) does not recover, no matter what you do. r. One can only look to new growth for indications that the problem has been corrected.

3. High Light ‑ yes, it's true, you can give our faves too much light. Cannabis does not receive full sun from sunrise to sunset in its natural state. It is shaded or given reduced light levels because of adjacent plant material, cloudy conditions, rain, debris and dust collection on the leaf surface, twilight periods of early morning and late afternoon, and light intensity changes caused by a change in the seasons. Too much light mainly serves to bleach out and destroy chlorophyll as opposed to causing leaf cupping, but it often goes hand‑in‑hand with high heat for indoor growers. Again, back off on the light and concentrate on developing/maintaining an efficient and robust root system. Keep in mind that all but equatorial material receives less light during flowering than during the vegetative stage.

4. Overwatering ‑ this practice only serves to weaken the root system by depriving the roots of proper gas exchange. IOW, the roots are not getting enough oxygen which creates an anerobic condition causing root decline and root rot with the end result showing up as leaf stress, stunted growth, and in severe cases, death. <gasp!> A lot of times folks think the plant is not getting enough plant food (which it can't under such adverse conditions), they add more nutes as a "curative", and just add insult to injury.

5. Underwatering ‑ not only is the plant now stressed due to a low supply of adequate moisture, but carbohydrate production has been greatly compromised. Step up the watering frequency, and if need be, organic growers may need to soak the pot from the bottom up until moisture levels reach an even consistency throughout the medium especially with mixes that are heavy in peat. If severe, a little surfactant (1 teaspoon per gallon of liquid Ivory dish soap) added to the drench will help return the organics to a normal moisture retentive state. If the pot feels light to the lift ‑ it's time to water. Don't wait until the soil pulls away from the sides of the pot or leaves droop before you water. Soil should stay moist (not wet) at all times. Wet/dry cycles cause more problems than you think they might solve.

Happy gardening,
Uncle Ben
 

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