Need recipes, please

Hughesville, MO(Zone 5a)

I can buy Triple Strength Phospate, Potash, blood meal, bone meal, alfalfa meal, etc. at my garden center. I would like some recipes for making my own 6 - 24 - 24 & 13 - 13 - 13 fertilizers so I don't have to use the salt based ones from the farm supply store. I would like a 6 - 13 - 13 for my iris and a good rose one too if anyone knows how to formulate them. Math is a very weak subject for me. Thank you for your help.

south central, PA(Zone 6b)

Here are some recipes - you need no math:
http://www.creativehomemaking.com/gardening/organic-fertilizer.shtml

The strengths you are looking for are difficult to find in organic fertilizers. You can just apply more, but I don't know if you really need it. Irises like a 5-10-10 and roses 4-4-5 - something like that.

If you WANT to do the math, here's an example:

Given this recipe:
3 parts blood meal
3 parts steamed bone meal
1 part kelp meal
1.5 parts Sul-Po-Mag

First, find the NPK on the bag or container for each ingredient:
blood meal is 13-1-0
bone meal - 1-20-0
kelp meal - 1-0-2
Sul-Po-Mag - 0-0-22 (plus it has magnesium and sulfur, but we're not calculating that)

Note, for example, 13-1-0 means 13% nitrogen, 1% phosphorus, 0% potash, which you probably already know : )

Now to find the NPK of the whole recipe, start by figuring out the percentage of N - nitrogen:

First, add the parts: 3+3+1+1.5 = 8.5
Then, 8.5 times some number (the percentage of nitrogen, “X”) equals the sum of each part times each percentage. (Percentages are changed to decimals in the formula.) Written out it is:

8.5 (X) = 3(0.13) + 3(0.01) + 1(0.01) + 1-1/2(0)
8.5 (X) = 0.39 + 0.03 + 0.01 + 0.00
8.5 (X) = 0.43
Divide both sides by 8.5:
X = 0.05
Change 0.05 back to a percentage:
X = 5%
So, the percentage of nitrogen in the total recipe is 5%.

Then, if you use the same formula to calculate the phosphorus (P) and potash (K) in the recipe, they turn out to be 4.9% and 4.1% respectively. So, rounding off the numbers, the NPK for this recipe is 5-5-4.

OK, are you nodding off? Or, wanna figure out the NPK for the other recipes in the link? Here’s some NPK values for the other ingredients.
Cottonseed meal NPK = 6-1-1
Greensand NPK = 0-0-3
Fish meal NPK = approx. 9-4-4
Meat and bone meal = 8-5-0 (Not sure about the potash in this, could be 0)
Soft phosphate = 0-33-0

Hughesville, MO(Zone 5a)

Thanks. I'd have to have a calculator and tutor to figure out all of that. LOL I really hate that nearly all commercial fertilizers are salt based. Even Miracle Grow.

Comer, GA(Zone 7b)

Geez I just gave myself a headache trying to figure that one out, me thinks I need to look into calculus if I'm going to do that again. I'm gonna stick to ground leaves coffe grounds and egg shells in my compost and let the worms do the rest

south central, PA(Zone 6b)

No calculus needed! : )

I like to play with numbers, but, honestly, I often forget all that and just use 1/2 the recommeded rate for organic fertilizers and as much compost as I can (never having nearly enough).

leaflady - the Sul-Po-Mag is a mineral salt too. Wouldn't there be salts in fish meal (if from the ocean) and kelp?

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