Question about concocting my own fertilizer recipe

[Jubaea_James760]

Was thinking about going organic ( down to earth fertilizers ) this year with my palms & cycads & had a question.  Everything would be in 5 pound increments, so if I add 1 fertilizer, lets say 6-2-4  & I add another, 8-5-8 does it compound to 14-7-12 or does it just equal out & add up the remainder?, if that makes sense to 8-3-8? 

 

Also, if anyone makes there own fertilizer from Down to Earth & cares to share they're recipe it'll be much appreciated. 

-James

[Banana Belt]

From https://en.wikipedia.org/wiki/Fertilizer

NPK rating is a rating system describing the amount of nitrogen, phosphorus, and potassium in a fertilizer. NPK ratings consist of three numbers separated by dashes (e.g., 10-10-10 or 16-4-8) describing the chemical content of fertilizers.^[22][23] The first number represents the percentage of nitrogen in the product; the second number, P₂O₅; the third, K₂O. Fertilizers do not actually contain P₂O₅ or K₂O, but the system is a conventional shorthand for the amount of the phosphorus (P) or potassium (K) in a fertilizer. A 50-pound (23 kg) bag of fertilizer labeled 16-4-8 contains 8 lb (3.6 kg) of nitrogen (16% of the 50 pounds), an amount of phosphorus equivalent to that in 2 pounds of P₂O₅ (4% of 50 pounds), and 4 pounds of K₂O (8% of 50 pounds). Most fertilizers are labeled according to this N-P-K convention, although Australian convention, following an N-P-K-S system, adds a fourth number for sulfur, and uses elemental values for all values including P and K.^[24]

So if you have a 50 lb. bag of  6-2-4  & I add another 50 lb bag of 8-5-8, in a 50/50 basis it would be (3 lbs N, 1 lbs P, 2 lbs K) + (4 lbs N, 2.5 lbs P, 4 lbs K) or total of 7 lbs N, 3.5 lbs P, 6 lbs K in 100 lbs (two 50 lb. bags).  Adding the two different bags completely together would then ben a 7 - 3.5 - 6  NPK fertilizer.  If you add other fertilizers or compounds just keep tally of the weight of each item added and the weight of the components and then divide by total weight of final product.  If you want to boost one compound above the others be sure to compensate down the reduction of the others respectfully.

[Jubaea_James760]

Thank you!

[Banana Belt]

8 hours ago, Jubaea_James760 said:

Thank you!

I make various mixtures of all kinds of different fertilizers usually from raw materials gathered from nature, pumice, rock flower from basalt, granite, phosphorite etc. which give the Potasium and Phosphorous and trace elements.  Composition from Rock or geologic sources are estimated from geochemical compostion listed in publications and reports, but natural nitrogen sources from manure, Kelp, compost and others are more difficult to determine % Nitrogen so I guess.  Nitrogen from natural sources usually contain lower amounts compared to synthetic or man made nitrogen compounds such as Urea, but not always. 

[Jubaea_James760]

Appreciate your insight. I'm leaning more towards organic fertilizers this year & already have lime & some epsom salt, which I generally add a little throughout the year. 

Thanks again 👍

[GregVirginia7]

On 1/26/2023 at 9:42 AM, Banana Belt said:

From https://en.wikipedia.org/wiki/Fertilizer

NPK rating is a rating system describing the amount of nitrogen, phosphorus, and potassium in a fertilizer. NPK ratings consist of three numbers separated by dashes (e.g., 10-10-10 or 16-4-8) describing the chemical content of fertilizers.^[22][23] The first number represents the percentage of nitrogen in the product; the second number, P₂O₅; the third, K₂O. Fertilizers do not actually contain P₂O₅ or K₂O, but the system is a conventional shorthand for the amount of the phosphorus (P) or potassium (K) in a fertilizer. A 50-pound (23 kg) bag of fertilizer labeled 16-4-8 contains 8 lb (3.6 kg) of nitrogen (16% of the 50 pounds), an amount of phosphorus equivalent to that in 2 pounds of P₂O₅ (4% of 50 pounds), and 4 pounds of K₂O (8% of 50 pounds). Most fertilizers are labeled according to this N-P-K convention, although Australian convention, following an N-P-K-S system, adds a fourth number for sulfur, and uses elemental values for all values including P and K.^[24]

So if you have a 50 lb. bag of  6-2-4  & I add another 50 lb bag of 8-5-8, in a 50/50 basis it would be (3 lbs N, 1 lbs P, 2 lbs K) + (4 lbs N, 2.5 lbs P, 4 lbs K) or total of 7 lbs N, 3.5 lbs P, 6 lbs K in 100 lbs (two 50 lb. bags).  Adding the two different bags completely together would then ben a 7 - 3.5 - 6  NPK fertilizer.  If you add other fertilizers or compounds just keep tally of the weight of each item added and the weight of the components and then divide by total weight of final product.  If you want to boost one compound above the others be sure to compensate down the reduction of the others respectfully.

🤔😳😵‍💫

[GregVirginia7]

5 hours ago, Jubaea_James760 said:

Appreciate your insight. I'm leaning more towards organic fertilizers this year & already have lime & some epsom salt, which I generally add a little throughout the year. 

Thanks again 👍

I use handfuls of Epsom salts on everything, maybe once a month…I do like molasses in the watering can as well for microbes in the soil but just got my 20 pounds of PalmGain 8-2-12…very ignorant about fertilizers but do understand benefits of the NPK combinations in the palms overall growth and health…always wonder about the best formulation though.