Elemental phosphorus sources

My question is, where can I get the elemental form of phosphorus? The nutrients in crab and lobster meal will not be useful my plants for a long time in its current form. I could put it in a ball mill for a week or two. That may help.
It’s hard to find information on the internet about the form of phosphorus we use. White phosphorus is so cool that it dominates the search results. I believe we use red. I’ve searched chem supplies on the web. no results. Kelp meal is another choice, do you think that is soluble enough to feed the soil? I have potassium nitrate 99.7% technical grade air milled and 325 mesh. Wollastonite is on the way. Dark Sedge peat and builders’ sand. What the heck am I up to?


Add bone meal to your soil


I would look for a phosphate salt. Elemental K is unstable. I remember one form has to be stored under water because it reacts with air. And I remember a jar of Na that I think was stored under oil. Been a while since those days of cleaning up abandoned labs.

:point_up_2: what @Autofreak suggested :love_you_gesture:


Good for your outdoor gardening in the ground. Like lobster/crab meal the bits you can see with your eyes will not break down in a useful way for containers or pot planting. You should till those types of amendments into your poor garden soil when you start a garden. Never till again. The larger pieces feed the soil for years.
I got suspicious when I saw little red pieces of lobster shell. I never saw a red lobster shell until it’s been cooked. Those red bits are in there for the guy with the money.
I’m stuck on soil. In a good way. 35 min. boring webinars about soil. Soil 101, with Master Gardeners. No music or slow motion weed shots. Borring as hell but every few minutes, Ah HA! that makes sense. Then there’s WTF, but I always heard…
It’s a good way to add to what I learn here. (Pot planting) I just caught that. Punny

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Not sure I understand the statement of it’s good for outdoor soil…same goes for indoor pots or fabric bags. What’s your intent… an organic soil/living soil :love_you_gesture:

White is used in tear gas and other nasty stuff. Take it out of water or mineral oil and it starts combustion. You can’t put it out no matter what. You have to remove it or it will keep relighting. It dominates all my search efforts. Red phosphorus is all around us in one way or another. Carefuly scrape the striker from 1600 match boxes and you may get an ounce. I suppose I could shred the strikers. Maybe just soak them and make the next tea guaranteed to produce massive yields Dude. lol
you never know.

It is my understanding that Phosphorus that is locked up in things like bone meal or crustacean meal need to be processed chemically (phosphoric acid) to change into something the microbiome can use quickly. The large grains in meals take a long time to break down. Excellent for a no till garden where you want a slow release of nutrients. Earth worm castings work the same way. Thats why they work so good. They time release throughout the grow. (90 days for autos).
In raised beds and pots we wash away nutrients every time we water unless we are adding them in. Time release of phosphorus would be great . The meals just take to long for auto flowerers.
I know I’m splitting hairs. I can be annoying. It’s my OCD.
Once I fully understand soil, nutrients, water, PH and the rest of the root zone, I’ll move on to above ground. Lighting, CO2 ect.
I could just throw some seeds in dirt. This is way more fun. I hope what I learn inspires others to do their own research.


I love the feedback, keep it coming. The wtf? moment that got me interested in phosphorous was this. It was pointed out that all the tomato bloom and rose bloom fertilizers on the market think you need a different amount of phosphorus to make your plant flower and fruit. The middle number on the package is what I’m looking at.
4-8-4, another brand recommends 12 - 55 - 6 and another, 3-9-4. And my favorite 0-53-0.
Can you see my dilemma? I need to find a balance of nutrients that makes sense.
Knowing what nutrients cannabis needs when, and how to get it to them. That is the question.

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If you want it ready available try wood ash. It is water soluble and will burn the sh*t out of your plants if you put it on living plants at a rate of more than a few grams per pot. It will also buffer alkaline so I would once again suggest just a few grams per pot and chicken scratching it into the top soil. If adding it to living plants.

I usually add it in the off season while my beds are fallow; or sprinkle it into my soil mix before it has roots in it.

It also has calcium, magnesium, and potassium. All things most of us have to add growing cannabis. I like ash because it’s free (if you know anyone with a wood stove or fire pit) and you only have to chase one rabbit instead of 3-4. It’s all in the wood ash. Pulverized; like you ran it thru the ball mill you mentioned.

I have a black walnut tree in my back yard. I read that you should never add it to compost or use the ashes. Whoops too late. It didn’t seem to do any harm to my tomatoes. I did the same thing in my garden with ashes more or less every year, until I moved this past year. I now live on a mountain of solid rock. Homes on my street don’t have much grass growing if any. I had to learn more about raised beds and containers. I’ve kept house plants alive but that’s about it for indoors as well.
Ash is an option. I’m looking for a diy based more on science than folklore, and that’s got some cred. Thanks again


Only fresh black walnut is a problem. If it’s aged on the ground a season (no fresh sap) you can even put the branches in a fish tank. Yes I do this. Have a tree out front. Burt to ashes, not a problem. Old dried out leaves not a problem.

Fresh leaves and wood. Better than roundup. Although interestingly my rose of Sharon (temperate hibiscus) grows happy as a clam about 2ft from my 60ft black walnut tree. Go figure…?

I have some helpful squirrels who pick up all the walnuts and bury them across the street in the woods. They save me a twisted ankle when cutting the grass.
Now that I think about it, I planted morning glory along the fence on both sides of the black walnut tree. They barely grew and never produced a flower. The seeds are pretty old but maybe it was the tree.

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Bat guano is another source which is in alot of different soils that are cannabis friendly. Not sure if you can buy just bat poo. doin my own research now as a result of this thread.

Foxfarms has a bag of only Bat Guano. 0-5-0 with myco and humic acid.

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Does NPK Raw Phosphorus fit the bill?

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I found out that we use Phosphoric acid for plants. Phosphorus is chemically altered to make phosphate, p2 05.
You can pretty much find nitrogen everywhere. It’s up your nose right now.
Ammoniacal and Urea Nitrogen can be found in castings and other sources and that’s what plants need. A little EWC in your soil mix should last you more than enough time to raise an annual plant in a container.
Don’t overcomplicate things by adding a bunch of crap to your soil that you don’t need and can do more harm than good. I got caught up in trying to be a soil chemist and bottony expert instead of keeping things simple. Good luck.

A little late to the party, but a couple of thoughts from a former chemistry major a half century ago. (Gooch 99 touched on this.) Elemental or white phosphorous, AKA :willie pete", is nasty stuff. It was heavily used during the Vietnam war, 'cause once it gets burning, it cannot be put out. Dropping it in water will create an explosion. Even the humidity in the air will set it off, so it must be stored under mineral oil. And if you go looking for this stuff on line, you will end up on someones watch list.

Now if you want a high phosphorous additive, the “P” in N-P-K, bone meal is the best/least harmful at 0-10-0… You can even get triple/super phosphate, 0-48-0 off Amazon.

Right on. The NPK Raw versions are specifically for plants. Idk what they’re made of, but they are inert, dark colored powders. They are the only thing I’ve seen (until your post) that will enable me to adjust one NPK number at a time. They also make complete veg and bloom nutes. I use their Raw yucca as a wetting agent. All high quality products.