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fertilizer Determining How Much Fertilizer to Apply to Garden Plot

Whats up everyone, this year I decided to get my soil tested and that came with a slew of super science I had to get interpreted for me. But in my quest to figure it out, I learned a thing or two about determining proper fertilizer amounts and found an article that broke it down.

Basically, I really payed no attention to the actual N-P-K Numbers, just figured if I wanted to focus on Nitro, I would get one with a higher N, etc....BUT, those numbers mean something! :lol:

Basically, the number represents a percentage of the total amount of nutrients in the soil if fertilized as per the recommendations. So as an example, if you need 1 pound of nitrogen per 1,000 sq ft, you need some algebra, but here is the formula. You can't really find pure N, so you need that from one of the million different types of fertilizers out there.

Feeding.jpg


Once I saw this it made it super easy to determine how much I needed to apply based on the size of my plot. I am gonna pick up some bloodmeal and that is 12-0-0, so I will just plug .12 into the equation for my N content, and my plot is 16x22, or ~350 sq ft. This means that in order for me to get my recommended 1 lb per 1000 sq ft, I need ~3 lbs (2.91) of the fertilizer to meet my requirements.

For some, this may be a no-brainer, but I figured it may help explain it a bit for those who don't really think much of the numbers.

Here is the full article.
http://www.google.com/url?q=http://ces.ca.uky.edu/oldham-files/DETERMINING_HOW_MUCH_FERTILIZER_TO_APPLY.pdf&sa=U&ei=XGl2T_CxDJHTgQfRnvCBDw&ved=0CAQQFjAA&client=internal-uds-cse&usg=AFQjCNE5ZSjhusA7C1SxCgcwPZapP8AWrg
 
hmm, interesting, I just picked up a brochure today to get my soil tested, need to go out tomorrow and grab the samples, then I am going to call the university to ask them what the turn around time is and a few other things about the test. I have a nice big bag of organic tomato/veggy fertilizer that is itching to go into the ground so it can all be broken down and soaked into the soil by the time I plant out, at least part of it, then I might do a small amount dressed on top to have slow release for the rest of the season, it depends on what the test comes back as, but I want to see where everything it at so far.

and Matt you can get pure N, I was looking at it because I had mixed a super tiny bit up mulch into the soil to try to loosen up the heavy soil a little bit, and I had a ton of mulch from a tree that was cut down, but anyways since I know it might leach out some N, I was looking around for some so when I get the test done, I might add some extra N so that the soil doesn't become N deficient when the mulch starts breaking down, but the last 2 years I went crazy with the synthetic fertilizer figuring it would make my plants bigger, which it did, but they could have produced more pods I think with less lol. oh well

but the more N stuff is used for lawns.. or you could always just get bone meal..
http://www.agway.com/catalog/home_and_garden/fertilizers/4_stage_fertilizers/10209991_agway_organic_stage_1_natural_fertilizer_40lb.html
or something crazy like this lol http://www.agway.com/catalog/home_and_garden/fertilizers/lawn/10212855_agway_greenlawn_lawn_fertilizer_30-0-3_15m.html
 
I must have misspoke, I meant like a 1lb of fertilizer is 1 lb of N. I got nitro fertilizer (12-0-0 bloodmeal), i was just referring to something that was by weight N. I guess it would have to be 100-0-0 in order to be 100% N.

I would recommend waiting to amend your plot until after you get the results. I was told that I needed 1 lb per 1000 sq ft of N, and that I was borderline on K. After talking to the university Hort rep, she said that I should avoid P all together. If I would have got a fertilizer that had a P ratio that was really anywhere above 3 or so, it would be hurting the soil.

I am just saying if you are going through the trouble to get it tested, you might as well give the recommended amendments.
 
I must have misspoke, I meant like a 1lb of fertilizer is 1 lb of N. I got nitro fertilizer (12-0-0 bloodmeal), i was just referring to something that was by weight N. I guess it would have to be 100-0-0 in order to be 100% N.

I would recommend waiting to amend your plot until after you get the results. I was told that I needed 1 lb per 1000 sq ft of N, and that I was borderline on K. After talking to the university Hort rep, she said that I should avoid P all together. If I would have got a fertilizer that had a P ratio that was really anywhere above 3 or so, it would be hurting the soil.

I am just saying if you are going through the trouble to get it tested, you might as well give the recommended amendments.

ohh ok I gotcha, yeah I have been wondering what the difference in the numbers are, I know it is the strength of the fertilizer, and so 12-0-0 blood meal would be what in the decimal form of the equation? .23? or just 23? but thanks for the heads up, that is interesting about the P hurting it, luckily I got a vegetable fertlizer with all low numbers, but after nuking the garden the last 2 years with ferts, and I will be adding cow manure at some point this year, but I will have to get that soil test in asap before anything else, should be interesting to see what pops up, and the difference it should make this year

thanks man!
 
You take the number (which is a percentage) and plug it in. So for my 12-0-0 it would be .12.

This means that applied to a 1000 sq ft plot at the appropriate weight, your soil would contain 12% N.

If you had a 6-0-0 Fert, it would take double te weight to meet the same requirements. For me and my plot I need about 3 pounds of the 12-0-0 bloodmeal. If I had 6-0-0 bonemeal or some other Fert, I would need 6 lbs to meet my N requirement.

When you get your results it will tell you what you need, an it should be in lbs per 1000 sq ft required. Just plug the numbers into the equation and it will tell you how much you should spread to be spot on.
 
nice sounds good, thanks, can't wait to get the results back, I just potted up another... 60+ plants into solo cups lol and moved the plants around in my tent so I could move the fan over to the other side, it was hitting the big Bulgarian Carrot plant, which has some nice ripe pods on them! had one just now, and going to wait a few more days for them to turn a little darker orange, they really burn a lot more when they get darker orange rather than bright orange/yellowish.
 
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