NPK values (nitrogen, phosphate, potassium)

I’m attempting to learn NPK values and the best way to introduce it to these new girls I just planted.

For absorption I had an idea to grind up the nutrients and sprinkle it on top of the soil for when I water since I will not be using a slow drip system. (Recommended on nutrient bags to place by drip system)

I have three bags. Nitrogen 46-0-0, Phosphate 0-46-0, and potassium 0-0-60 which makes:


How can I calculate the best possible outcome for weed growing. I’m growing blueberry haze if you want to get genetically technical.

Any tips and ideas on how to dial this in for best outcome? Anything is greatly appreciated. I will attach a picture so you can see what I’m extactly talking about.

Happy growing and thank you for the guidance!


You do NOT FEED seedlings. Not until maybe 3 weeks in, you will burn them. They grow just fine on their own without nutrients until they NEED NUTRITION…
What you are asking is not an easy thing becasue requirements change based on the genetics of what your are growing, the environment, the soil, lights, Rh and stage of growth
You can make a basic formula for VEGGING, another for FLOWERING and a final one for Late FLOWERING… You will still need micro nutrients and minerals. Do not forget to get some blackstrap molasses and maybe cal/mag. Kelp is a great addition too
Here is the key…when you make a feeding solution, you can use a tds meter to see what the PPM is of the solution you created. You have to do that for all 3 products; N, P, K. Add them together and again,see the tds / ppm values of your finished solution. One of the issues is WATER SOLUBILITY. Not all nutrients are water soluble, some are only sprinkle on soil (top dress). Then when you water, it permeates the substrate (soil). You could “google” the best nutrient values for the 3 stages and try to meet them.
So, you can see, it is not as easy as…add a teaspoon of each to water, mix thoroughly and water the plants.


Top soil of these lil girls will be removed. Thank you. I’ll do more research :ok_hand::call_me_hand:

Have you heard of liquidirt? is liquidirt like cal/mag What do I do with black strap molasses? Kelp?
I’ll get a meter, I just got an HM PH meter.

:call_me_hand:Thank you

I have heard of Liquid dirt…Only thing I hear is that it is messy. It got GREAT reviews and being ORGANIC, takes away the fear of OVER FEEDING
Blackstrap Unsulphured (no sulphur dioxide for preserving) molasses is known for its iron content—one tablespoon per gallon of water — it is also a rich source of natural calcium, magnesium, and potassium. It is also a good source of manganese, vitamin B6, and selenium.
KELP - (liquid) * stimulate growth, and even help produce more fragrant flowers & sweeter fruits

  • Designed for use in all hydroponic systems, aeroponics, coco-coir, all soil-less mediums such as vermiculite, perlite, and in soil
  • This product allows your plants to more effectively draw nutrients from the soil, leading to bigger and better harvests, an abundance of flowers on flowering plants, and overall healthy happy plants.

I ordered the blackstrap molasses. If I use this will I still need a calmag supplement? Do you have any recommendations for calmag or could I use liquidirt instead? I will order some kelp. Do you have any brand recommendations?
My plants will be eating better than me.
I can’t wait until I have the knowledge of my two HM devices to read the pH and TDS (what’s TDS stand for? Time to google :sweat_smile:) I’ll have to watch some videos. Again I can’t wait to have all this knowledge embedded in my brain :grin:. Has anyone here taken any agriculture classes? Botony?
Happy growing everyone!

P.s. I scraped the nutrients off the top layer and flushed

TDS - total dissolved solids…the particle makeup of the nutrients in your water based on amount per measurement of water
CalMag…@Kronic has a homemade DIY version,watch his video clip. Many of us use eggs shells, pulverized, soaked in an acid (vinegar, lemon juice) then add Epson salt and you have calmag for a PITTANCE OF THE COST OF MANUFACTURED.
I would go for the liquid dirt…Organics are the safest and least likely to burn you plants
Kelp - liquid…ask @MDBuds, he has great recommendations. I use Alaskan fish, Kellogs, etc…I am not particular. I even use organic kelp powered for consumption and mix with water, mist my plants weekly

Neptune’s Harvest Fish & Seaweed Fertilizer

Alaskan Fish fertilizer
to name a few


Veg 3-1-1 bloom 1-3-2 flower 0-3-3 are the basic NPK guidelines I follow. This will work for all strains as a basic system but to get it dialed in strain specific some tweaking will be required.

Without a closer picture or more information about the nutrients I can’t really say how much to top dress with or how much to mix with water at each stage for the desired npk ratio.


@Mrb53004 most liquid kelp is pretty much the same. The only difference between brands usually is slight variations in npk and micros dependent on processing methods and where the kelp was sourced.

I’ll use just about any liquid kelp that’s organic but at the moment I’m fond of GS Plant Foods organic liquid kelp. It’s inexpensive comparatively to other brands and easy to find.


I have a whole bag of kelp because I use it in my mushroom broth. Now y’all have me over here going, “Well, it already smells a little like horse manure. It won’t hurt to start another jar.” Does it work like that? Just ferment it?

PS: I just smoked since a migraine is attempting to appear, so my reality is eschewed.


First mistake made on second grow. Starter pots too small I believe.

I’ll have to watch a video on the explanation of the NPK numbers and how to tweak. I don’t understand how using this TDS Meyer will measure each nutrient and give you a number based on how concentrated it is. My TDS Meyer showed 174 TDS at .5 with a light concentration of liquidirt. Seems low? How do I put all of this information to use. Does anyone know of a video for explanation ? One of my little girls had an issue coming out of the seed pod and is struggling :pleading_face:
Thanks for all the help guys!
Got my kelp and ordering a sprayer :ok_hand:

@KriZm if you can take a closer photo of the labels and ingredients for your nutrients I can help more. I use organic dry amendments to make teas and to top dress so I’m familiar with how to mix.

I just need more information. Those appear to be chemical salts though so I just wanted to make sure before I told you how I would mix and top dress.

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I will attach the pictures I took this morning for your professional guidance :blush:

I can’t wait to have the skills and knowledge you have or some of them :ok_hand:

I’m attempting to learn ph levels and what tds readings mean and what to do with those levels. I checked the pH and TDS of a LA CROIX sparkling lemon water. It had a ph of 4.2. now is that bad or is that because it had lemon which is accidic so it dropped the pH ? The TDS would fluctuate between 350-380 at the .5 setting so you would double that right ? Lol so lost. Either way. What do I do with this information. Was the high TDS from the bubbles or actual minerals ? Is the ph too low to be absorbed by my body because of the lemon? I do piss a lot when drinking them as if they go right through me. I’m assuming it’s the same concept for humans and plants.
Anyway lol, any clarification would be amazing.

I think 2 of my girls are gonna crash. the littlest one is just not catching the soil and is struggling. One girl has a mental disorder and is it’s trying to catch light from the left side even though the light is directly above. :roll_eyes:.
The other ones are fine but the pot is so small that I they can dehydrate quickly. I will never use pots this small again. Wtf are they even for? Maybe soil that holds moisture better.
Thanks for your time MDBuds!

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What is your substrate and watering method? Important to know what you planted them in as it can and usually does change things around
I use the same nutrients and have worked out my formulas but right now, I m doing a comparison grow using a liquid dirt vs a manually formulated mixture. What you soil composition is makes a big difference. My goal is to start in FFOF (foxfarmoceanforst), some coco (maybe 20%…or peat if you are not ecologically concerned), worm castings (from a local source where I get my worms for my garden). I hope to plant and WATER ONLY with plain water until flower, then liquid dirt for the remainder. Molasses and cal/mag (@Kronic home made DIY) foliar spray still in use as is occasional kelp and humic acid to keep my soil living)
Lemon (and vinegar) are acidic and bring down the Ph. Ph should be 5.8-6.5
TDS changes depending on nutrients, molasses, liquid seaweed/ fishmeal, etc…anything additional you put in the mix…IMPORTANT - only 1 thing at a time, never mix nutes together and then water, make solution and add nutes, 1 at a time, recheck ph, aerate for 12/24 hrs…good to go

@KriZm you’ll be safe using the top dress amendment rates suggested on the packages. Just use the single plant/container plant instructions and water it in with your kelp/molasses/water.

For the kelp and molasses a safe feeding rate that won’t burn is 1 tsp per gallon every watering and feeding.

The liquid dirt I would stay away from until it is time for flower. Once it is time for flower cut out the nitrogen and just feed with your phosphorus and potassium and water it in with the liquid dirt mixed with your normal watering at the specified applications rates for container size etc.


Thank you!
When should I start using the kelp/mo water?
Will this mixture be my normal watering mixture from now on?
What about a kelp spray ? Do you do one?

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@KriZm I use that low mixture for all or of my waterings seed to harvest personally. I think it brings out the terpenes better than the large 2 tbsp feedings every 4 weeks.

I do kelp foliar sprays as well yes. They work wonders. I mix it with my calmag when I foliar spray calmag. Get some damn stinky plants that way. Lol

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With the NPK nutrients I have available, do you think it would be better to put it in water (put it in a 2 gal jug and shake then check ph level before application)(maybe with the kelp/mo mix or plain water)or just on the top soil when watering and try to water on top of the nutrients with the kelp/mo mix. I could also use the pestle/mortar to help it dissolve in water? (Maybe unnecessary)

@KriZm only a few of your nutes are soluble enough to make a feeding solution. You’d be better off top feeding dry and watering it in as most of the packages suggest.

Another benefit to top feeding is less waste and less risk of nutrient burn because it takes more time to break down and has to work its way through the soil to the roots. If applied appropriately that is. Top feeding and top dressing takes a week or two to start really seeing an effect so be careful not to top feed more than once every two weeks because it can add up and eventually start causing nutrient burn and lock outs.

It’s a common mistake growers new to top feeding make so be patient and only increase your feed after two weeks if you see deficiencies otherwise feed the same amount. If you see excess or surplus or some burning just hold off on feeding for another week and give a lighter feeding.

Hope this helps you man. Happy growing. :v::call_me_hand::metal:


Thank you so much! Happy growing! Greatly appreciated!
I moved the plants into their home pots and I hope the ones that aren’t doing so well somehow snap out of it and get going and if not it’s a learning experience :blush: stay humble.

Thank you again!

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