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NPK Fertilizer mixing

Posted by mmhm 6 (My Page) on
Sat, Apr 5, 14 at 17:46

Ok I am new to mixing up fertilizer in terms of making N-P-K.

I bought:

1. Urea Nitrogen Fertilizer 46-0-0 Granular

2. Monoamonium Phosphate Fertilizer (MAP) 11-52-0

http://www.ebay.com/itm/FERTILIZER-20-LB-MONOAMMONIUM-PHOSPHATE-MAP-11-52-0-LAWN-GARDEN-FOOD-PLOT-/321370824878?pt=Fertilizer_Soil_Amendments&hash=item4ad331a0ae

3.Potash 0-0-60 Potassium Fertilizer

http://www.ebay.com/itm/Potash-0-0-60-Potassium-Fertilizer-20-lbs-lawn-garden-plant-food-plot-wildlife-/221409600361?pt=Fertilizer_Soil_Amendments&hash=item338d0a6369

If I mix all these 3 same amount like 1lb from each, will I get N-P-K = 57:52:60 ?

With this combination, what amount ( lb or gm or tsp ) I should mix with per gallon of water to get 28.6 : 26 : 30 to get plat food for my garden ?

Thank You


Follow-Up Postings:

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RE: NPK Fertilizer mixing

Not being a chemist I rather doubt it's that easy. Probably a lot more involved in the calculations.


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RE: NPK Fertilizer mixing

As a follow up, how are those percentages calculated? By weight or volume? If by weight then you are going to have to factor that in.


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RE: NPK Fertilizer mixing

Agree the math is off but why would you want to use 28.6- 26-30 for your garden??? Is this a result of a soil test?

That is horrendously strong fertilizer. Don't the bags have any dilution instructions on them? And why mix them? If one of them is specifically needed dilute it to the label instructions and then again by half and by half yet again. For example that would get the N down to the normal level of approx. 5. P would still be high at 6 though.

Dave

Dave


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RE: NPK Fertilizer mixing

  • Posted by mmhm none (My Page) on
    Sat, Apr 5, 14 at 20:22

Ok I am really new to fertilizer. I went to lowes and home depot and found that, they are selling miracle gro (24-8-16) all purpose food. Which is N:24% , P:8% and K:16%.

http://www.homedepot.com/p/Miracle-Gro-1-5-lb-All-Purpose-Plant-Food-1001122/100081891

But I found the miracle grow little expensive for the whole season. So I bought the raw fertilizer and thinking to mix them to make equivalent to near to equivalent to miracle grow to use as plant food with cheap price. Please let me know what should I do and how should I fertilize my garden plants. I really dont want to buy expensive miracle gro.


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RE: NPK Fertilizer mixing

If you have a soil conservation office near you, call them and ask them about your soil. You could also do a soil test, but it seems like nobody wants to do that. I found out that my soil needs no Phosporus. In fact, the fertilizers being produced for the local area have no Phosphorus in them.

Another very important factor is soil acidity. If your soil is very acid or alkaline, you can pour a ton of fertilizer on, and it's not going to work real well. If you would tell us where you live, maybe we could predict what kind of soil you have.

You should get some opinions from smart people in your local area.Watch out for fertilizer recommendations on the web. There is a lot of BS out there. Yes, I know that BS makes great fertilizer.


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RE: NPK Fertilizer mixing

  • Posted by mmhm none (My Page) on
    Sat, Apr 5, 14 at 21:16

I bought the soil Ph meter and the soil is about 7 in Ph. I know the best Ph would be 6.5 so this summer, I will add dome Ph down solution to bring it down. And for soil, I bought all soil bag from lowes for the garden bed. I grew last year like tomato, eggplant etc. They were ok I mean the plant grew nice but the fruit was not that much. I added azomite in the soil but I am puzzle with what plant food I should use ? my post code is 14607.


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RE: NPK Fertilizer mixing

Just take the MG (24-8-16) recommendation for mixing in watering can. and try to interpolate a bit.

4'EXAMPLE: MG says mix ONE TBS per gallon. Now yours has almost TWICE AS MUCH nitrogen. So then you should use 1/2 TBS per gallon, to get an ALMOST 24: 24: 24 effect.

YOU can even mix unequal portions of your 3 items to get a 3-1-2 (Like MG) or any other ratios.

I am sure MG is making very conservative recommendations, b/c they don't want you to kill your plant and blame it them. But I would follow their foot steps as their chemist have done it properly.


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RE: NPK Fertilizer mixing

Ok, first the DIY test kits and meters are notorious for being inaccurate so the odds of your soil pH actually being 7 is slim. It is far more likely to be around 6.5 in your region and most vegetables will do just fine with a pH of 5.5 to 7.5. Mess with it based on that result and the odds are 10:1 you will only make things worse.

For less than the cost of the meter you can get a professional soil test done at your local county ag extension office.

Second your zip code is Rochester, NY which is garden zone 6a. Once you know your garden zone then all sorts of information is available to you.

Third, DOME Nutrifield pH up and pH down is a hydroponics solution, You are gardening in soil, not hydroponics?

Fourth, different plants need different nutrients and at different times of they year. How much of each you need to add all depends on what your soil lacks. Only a soil test can tell you that.

It is very rare that soil that is deficient in either Phos or Potassium is found but when it is only a small addition is usually required. Are there exceptions? Yes. But the only way you can know is with a soil test. Low doses of nitrogen can be beneficial for many plants during the season as it tends to dissipate quickly. But excessive nitrogen either burns the roots and kills the plants or gives you huge green plants with no fruit.

You are far more likely to kill all you plants with all that fertilizer rather than help them.

You would do better to return all those things you bought and instead till in several bags of good compost or composted manure and a bag some plain old cheap 10-10-10 or 10-0-10 granular fertilizer such as is used on lawns. It isn't ideal but far less dangerous than all the other stuff you have.

Dave


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RE: NPK Fertilizer mixing

Ammonium phosphate will lower your ph


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RE: NPK Fertilizer mixing

  • Posted by mmhm none (My Page) on
    Sun, Apr 6, 14 at 1:31

Dave,

Thank you so much for replying with details. But as seysonn suggest, why cant I follow that ?

I mean, in 10-10-10 or 24-8-16 all purpose plant food its said on its package, use 1tsp per gallon of water and apply water every 2 week. So lets say, I need 100 gallon of water for my total garden. So I need 100 tsp of all purpose miracle grow.

100 tsp = 490 grams = 1.08 pound.
Among this 1.08 pound (24-8-16) miracle grow, 24% or 0.2592 lbs is nitrogen(N) , 8% or 0.0864 lbs is phosphorus(P) and 16% or 0.1728 lbs is potassium (K)

Which means, if I buy miracle grow, I am applying this ratio of 24% Nitrogen with 100 gallon of water and so on for P and K. Or I can say, I am mixing 0.2592 lbs N with 100 gallon of water and applying every 14 days to my garden.

So now I have 46-0-0 urea (nitrogen) , 11-52-0 Phosphate (11 N, 52 P, 0 K), 0-0-60 Potassium

and if I mix 0.0864 (0.2592/3) lbs urea, 0.01329 ( 0.0864/6.5) lbs Phosphate, 0.04608 (0.1728/3.75) lbs Potassium

with 100 gallon and apply every 14 days and do the same math for , should not it work almost like miracle grow ?

Otherwise Miracle grow disclaimer would be wrong on packaging. Or am I missing some concept ?

Also pannu18, in your respond, miracle grow should lower the pH as well. But I did not see that on package that appling miracle grow lower the pH !!


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RE: NPK Fertilizer mixing

mmhm: "And for soil, I bought all soil bag from lowes for the garden bed. I grew last year like tomato, eggplant etc. They were ok I mean the plant grew nice but the fruit was not that much. "

If your tomatoes and eggplants didn't produce much fruit in new commercial garden soil, have you considered other potential issues that could have gone wrong besides fertilizer? How much sun they were exposed to daily, or how long the growing season was, how well draining the soil is, how healthy and deep were the roots, or if they received enough water.

The soil bags your bought are usually enriched. The first year, they don't need much. I grew tomatoes in commercial garden soil and they would just not stop making fruit.

In my opinion, the water soluble chemical fertilizers will degrade and create imbalance in your soil. There are other nutrients in the soil besides NPK that plants need. It can be detrimental to the plant's health to be fertilized manually. Over-fertilization; and dependency on regular fertilization (in inert soil) come to mind. Also, it's really complicated!

I use compost and occasionally boost with seaweed or fish based fertilizer.

In the fall or spring, I add compost from my pile and commercial organic composts to enrich the soil for the year.

My compost pile is mostly leaves and old coffee grounds and I'm very happy with this, but I started a worm farm this year (really just worms in a rubbermaid bucket with mushroom compost... the kids love it).

I use Alaska liquid fish and seaweed fertilizer because it's easy to buy at Lowes and Home Depot, and not too expensive. But the fish stuff smells pretty bad for a day or two though it doesn't bother me.


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RE: NPK Fertilizer mixing

If pay attention to the ratio of different macro nutrient in Miracle Grow all purpose plant food, it says 24-8-16 which roughly translate into 3-1-2, which is absolutely NOT the ratio your plant preferred in most of its different growth stages. P is far too high for its own good. Accumulated excessive P is a very difficult thing to deal with. Use something with less P.


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RE: NPK Fertilizer mixing

Dave, Thank you so much for replying with details. But as seysonn suggest, why cant I follow that ? Otherwise Miracle grow disclaimer would be wrong on packaging. Or am I missing some concept ?

You can of course try anything you wish to experiment with. All we can do is advise you against making the same mistakes some of us made when first learning about fertilizers.

Yes, unfortunately you are missing several concepts (like comparing solid granular ferts to liquid ferts when they work very differently) and you are making some faulty assumptions too with no basis in fact (like not knowing the nutrient levels of your soil and assuming your problems were even nutrient related). But unfortunately that is common for one new to working with fertilizers.

What is NOT recommended by all experienced gardeners is over-compensating, over-applying. fertilizers. That is consistently stated in various forms throughout this thread but that is what you are talking about doing in terms of amounts, form, and frequency of application. Sadly we know that always does far more harm than good.

But we can only warn and advise. It is up to you to decide which, if any, advice you take or ignore.

Good luck with your garden.

Dave


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RE: NPK Fertilizer mixing

  • Posted by mmhm none (My Page) on
    Tue, Apr 8, 14 at 15:09

Dave,

Thank you so much for all the good advise and all other in the forum to give me some good advise. I should have post it before I buy and unfortunately I cant return them as I bought them from ebay. But with all your advise, I would possibly just through them out and start all over again.

But anyways, so dave, please advise me if you would be in my position, what would you buy as plant food ? if you can give me a link from lowes or home depot, it would be really great.

Not sure if this will help http://www.lowes.com/pd_92129-1321-00051524602218_0__?productId=3047339

Also will I have to add this types of organic food every year ? Or one time is good for few years ?

Another thing please help me understand. So I water my garden every alternative day from normal tape water. But I have observed that, if there is a heavy rain, all plants grow really fast. Why rain trigger plant to grow faster than tape water ? I have tried plenty of water but still rain trigger heavy growth. I have tested the water pH of tape and its like about 7-7.25 in my area.

Thank You


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RE: NPK Fertilizer mixing

That is the point several people have made. We don't know your position and neither do you. You are just making guesses.

The only place to start is with a soil test so then you will know exactly what to use and how much. Most soil tests will show that nothing, or very little of 1 or 2 things are required. Keep the products you bought and once you have the soil test it will tell you what and how much to use.

If you refuse to get a professional soil test done then the only safe option left is to stick with lots of organic supplements like compost and composted manures, not fertilizers. .Supplements like the Black Cow Composted manure you linked above will provide any needed nutrients without the fears of over-application. But composted manure doesn't need to be that expensive either.Walmart, HD, Lowes and many other stores all offer several different brands of compost and composted manures. Link below is just one example of non-manured compost. Also see: http://www.walmart.com/search/search-ng.do?search_query=manure&ic=16_0&Find=Find&search_constraint=0

Also will I have to add this types of organic food every year ? Or one time is good for few years ?

Yes you will need to add them every year at least 2x a year. There is nothing you can add one time and be good for years.

So I water my garden every alternative day from normal tape water. But I have observed that, if there is a heavy rain, all plants grow really fast.

No one should ever water their garden every alternative day. Any experienced gardener will tell you that. Doing so only creates water-dependent shallow rooted plants with poor production. Vegetables require deep much less frequent waterings and only when they need it, not when it is convenient for the gardener or on some sort of fixed schedule.

But not all vegetables require the same amount of water nor do they all require watering at the same times and the needs vary greatly depending on the weather and the size of the plant and the stage of growth it is in. You need to learn how much water each of your vegetables require on a weekly basis at each stage of growth.

Plants appear to perk up from rain due to all the extra nitrogen in the rainy air. Your tap water is no different from most anyone else but the pH of the water makes little difference.

Hope this helps.

Dave

Here is a link that might be useful: HD - Mushroom Compost


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RE: NPK Fertilizer mixing

As Dave said, you need to get a soil test. And the PH meters aren't accurate. I have an expensive one and it will give me a reading of 7 but my soil tests at the lab give me a 6.

Another thought on the urea, I have saw bags of it at big box stores and it said "urea fertilizer derived from limestone". I'm not sure, but wouldn't that raise the PH? I was looking at them since my soil test said that I only need N, P is High, and K is a little high.


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RE: NPK Fertilizer mixing

Not sure if anyone mentioned but its very important to not feed high Nitrogen to most (non-leafy) vegetables. Its OK to provide higher N in the first 2-3 weeks but switch to low N when flowering starts

Here is a link that might be useful: Why you need Low Nitrogen


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