During downtime at work today I figured out the NPK value of my fert mix. Thought I'd share in case anyone wanted to do that and customize their mix. NPK values are based on % of mass. So 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! Sent from my SM-J700T using Tapatalk
I don't believe in separating veg and bloom in regards to nutrient application. with organics, things take time and especially the breakdown of organic matter and the availability of nutrients to the plant. What this means is that for the most part, nutrients added are not going to become available to the plants till much later. you are much better off IMO to be adding consistent inputs throughout the growing cycles which include everything and are not phase specific (flower/veg). If the soil has everything the plant can regulate and take what it needs when it needs it. Here are a couple of quotes on the subject from BlueJay (aka MOFO) who started the no-till thread. No-Till Gardening No-Till Gardening
Thanks for stopping by Sc00byD00bie. Generally I'm of the same mindset and I ignore NPK values for the most part. But as always I love to experiment and feel things out for myself, finding what works. This formula I have shared is for information purposes only (4 da curious cats) and isn't limited to finding the NPK values of a mixture. Sent from my SM-J700T using Tapatalk
I used a similar method for calculating the NPK ratio of my final mix. But I just used the recommendations on the boxes in cups and totaled the NPK value and adjusted amendment amounts to get a even ratio. I don't know if its accurate by any means but its a good exercise to do at least once I guess to become a little more familiar with meal mixes.
Hey 4ala2sk0a - I think this is a fundamental exercise in DIY gardening. Instead of buying a (ex. Dr. Earth's Flower Girl) store bought ready made fertilizer you can make your own and know exactly how to do it, not to mention how THEY do it. Good vibes to your garden! PB79er Sent from my SM-J700T using Tapatalk
Hi, sorry to resurrect a dead thread but I haven't found anything like this out there that doesn't cost money. I made an Excel sheet calculator based on the math in OP's post. It's in grams, but it can be Oz or whatever as demonstrated here. Sadly making a calculator that calculates amounts of given amendments for a given NPK ratio is beyond me, that's some linear algebra nonsense that I was never good at. But this calculator makes bruteforcing it trivial, you will find the way the numbers change is quite intuitive when lain out like this. OP's way of doing this is very handy and scalable to many amendments of different volumes, with ease. This is a thank-you. Google sheets