[ColaCalyx]

Topdressing dry meals in a organic soil grow is the ultimate in kick-back feeding for plants. If you build your own soil mixes from scratch, you're gonna have a lot of leftover amendments. Need an organic soil mix? Conveniently Organic Soil Mix https://www.icmag.com/ic/showthread....93#post8913593

Want to make a custom mix using a multitude of dry meals like : alfalfa, kelp, neem, fish bone, chicken manure pellets, etc? I'll show you how to make a mix, and teach you how to manipulate those NPK values.
You might not care about NPK, but using the same ingredients you're already using in your grow but tweaked for nutrient ratio isn't going to hurt, is it? Cycling additions is always a good idea, and switching topdressing inputs through the season will do just that.

Equipment:
All you'll need is a variety of meals, some measuring cups, and a kitchen scale. I used some typical meals used in organic gardening.

- Quick explanation:
NPK values are based on % of mass. Most soil recipes are based on measurements of volume (cu.ft, gallons). I took my unit of measurement (1Cup), which is a measure of volume, and weighed 1Cup of each of my meals to get the mass (weight).

Approx. weights of 1Cup of meal/NPK values:
Alfalfa - (5oz) 2.5 - 0.5 - 2.5
Kelp - (7.5oz) 1 - 0.1 - 2
Crab - (7oz) 4 - 3 - 0
Neem/Karanja mix - (6.5oz) 6 - 1 - 2
Fish Bone - (8oz) 3 - 16 - 0

Now multiply each value in a given NPK by the weight in ounces.
Ex. - Alfalfa weighs 5oz in a cup. N 2.5 x 5 = (12.5 ) P 0.5 x 5 = (2.5) K 2.5 x 5 = (12.5)
Do that for each meal.
Now add all the N values together. Then P and K.

The above values totaled:
111 - 158.75 - 40.5
Now add up the total amount of ounces:
5 + 7.5 + 7+ 6.5 + 8 = 34oz
Divide each NPK value by 34:

= 3.26 - 4.67 - 1.2
N P K
I'll use that for VEG.

For BLOOM I'll soften the nitrogen and even up the P and K numbers while adding sulfur and magnesium. I chose to use Langbeinite 0 - 0 - 22 aka sul-po-mag. I'll take 1 Cup of the above fert mix and add 1/3 Cup of Langbeinite.

So as before I'll weigh the 1/3 Cup of Langbeinite = 5.3oz

Follow all the steps before and multiply the NPK values by oz then add all the values together and we arrive at:
111 - 158.75 - 157.1 ÷ total oz (39.3)
=
2.8 - 4.03 - 3.99
N P K
So there you have it. Just more information for the tool box. Blessings farmers!
- ColaC

[h.h.]

Well done.

To throw in another factor. Nutrient availability. The mineralization rate of the individual amendments.

https://agwaterstewards.org/wp-conten...anic_Crops.pdf

[ColaCalyx]

Nice point, and thanks for posting that resource.

To customize the topdress further you can use additions that break down quickly, like alfalfa, or slowly, like feather meal. To that point, another thing that is mentioned in the resource you posted is surface area. Meals that are finely ground provide more surface area, which will help them break down quicker.
Looking at the NPK and % of water soluble vs water insoluble nature of the amendments will clue you as to how quickly the nutrition will be available to the plant, what % nutrition relies on breakdown through micoorganims, and how much organic matter it contributes - which tells you how much bulk it adds to the soil, eventually becoming humus.

[Mattbho]

If i post what I threw together do u mind taking a peek

[St. Phatty]

when the air is full of dust

light a lighter

see if the flame has any effect.

more importantly - don't breathe that dust.

[mexweed]

lots of variables, plant genetics will develop root systems that perform differently, some plants will be heavy feeders/fast drinkers, some will hold their moisture for a day or two longer than others during increased hot and dry conditions, anyone that has ever had AC malfunction during the summer knows there are the plants that look like nothing happened and the ones that almost die

the root structures interact with the microbes and available nutrients, in organic what you put into the soil isn't always what the plant uptakes, at least not as calculable of a NPK like hydro

if there is too much immediately available the microbes won't work as much on breaking down stuff to be available later, if something with too much immediately available gets mixed in an already good soil it can burn the plants, generally it's better to mix in stuff that will get broken down and become available as the base soil depletes

if something is too fine of a powder and someone is watering until there is a fair amount of runoff it will wash through the medium before getting broken down and used, fine powders can also wash down into the medium and clump together, this can inhibit moisture retention in the area which prevents nutrients in those spots from getting broken down as efficiently

the microbes present also play a major role, is there just some mycorrhizae or does it have a nice bacteria profile too

the top of the soil is what dries out first, the more mixed and distributed a nutrient source is throughout the medium the better balance of moisture and oxygen it will have, a primary feature of good soil is its moisture retention/aeration, it's important that the top layer is able to hold moisture

[Maple_Flail]

someone is using Down to earth ferts... LOL

ANYWAY... not accounting for long release, short release, and immediate releases. solubilty vs insolubility, microbial activity, PH flux, CEC, and carbon and/or sugar inputs

but GOOD starting point..

my word of advice. Start a Spreadsheet. may be frustrating the initial set up but once you've got your equations down in the automation its so much easier

[ColaCalyx]

Originally Posted by Maple_Flail

someone is using Down to earth ferts... LOL

ANYWAY... not accounting for long release, short release, and immediate releases. solubilty vs insolubility, microbial activity, PH flux, CEC, and carbon and/or sugar inputs

but GOOD starting point..

my word of advice. Start a Spreadsheet. may be frustrating the initial set up but once you've got your equations down in the automation its so much easier

DTE, a small hobby grower's best friend, lol.
Yeah there's a lot of variables with just the mix, not to mention environment....at some point I just say "good enough", because with organics you can't duplicate an exact NPK, or anything else for that matter.
Nice work with your spreadsheet. Do you consistently use the same companies for materials? I'm guessing you base your equations off of a sample of each material?
If you're making lots of soil mixes, serious about data, or doing commercial than seems a spreadsheet is the best way to do it.
Dry meals, a kitchen scale, and a calculator. If people have those items, they can use my quick n' dirty ballpark method.

[Maple_Flail]

Originally Posted by ColaCalyx

DTE, a small hobby grower's best friend, lol.
Yeah there's a lot of variables with just the mix, not to mention environment....at some point I just say "good enough", because with organics you can't duplicate an exact NPK, or anything else for that matter.
Nice work with your spreadsheet. Do you consistently use the same companies for materials? I'm guessing you base your equations off of a sample of each material?
If you're making lots of soil mixes, serious about data, or doing commercial than seems a spreadsheet is the best way to do it.
Dry meals, a kitchen scale, and a calculator. If people have those items, they can use my quick n' dirty ballpark method.

constantly updating the spreadsheet. once the math is fairly set its easy to plug and play numbers

input sources are always changing depending on availablity and budget at that moment.

it badly needs a revision, i still do a bunch of pen and paper chicken scratch to figure out whats in the dregs to topdress with when making tea. still use a fair amount that doesn't have npk testing.

i went this way to avoid the pile of notes i was accumulating..

[Robbig22]

Maple flail. I was looking at your spreadsheet and I see your ratio of npk and mag, the number above it nitrogen 1760 phosphorus 1053 and potassium 1745.How high do you want those numbers, I see how you got them but how high do you shoot for. Not sure if I explained myself sorry