Sciencemadness Discussion Board

MIRACLE GRO SOLUBLE PLANT FOOD

MR AZIDE - 10-6-2012 at 11:38


I ve got this for the back garden.

http://mcdougallshomehardwareoban.co.uk/store/image/cache/data/large_1_016922_miracle_gro_all_purpose_soluble_plant_food_1kg_by_scotts-500x500.jpg

On the back it only lists percentage of N, P, K etc....

IT is very deliquescent, and granular, its also dyed blue.

I can find no info as to what the actual chemicals are though.

Does any one know, if most of it is, actually Potassium Carbonate...???? ( which I suspect that is what it mostly is)

vmelkon - 10-6-2012 at 12:19

Try to look up their website (Miracle Grow).
I have looked at the site of another manufacturer back when I was interested in it and there wasn't shit.

Fertilizers tend to be a mix of KNO3, some phosphate and some dye and some other stuff. Some are dyed blue and some are dyed green. I guess there are other wonderful colors as well :).

Carbonate? I doubt it. I have mixed mine with HCl and there is no fizzing.

Also, you might want to read
http://en.wikipedia.org/wiki/Fertilizer

Vargouille - 10-6-2012 at 12:41

Not being able to see the actual fertilizer, I can comment that I had an orchid fertilizer that was blue from EDTA-chelated copper salts.

hissingnoise - 10-6-2012 at 12:57

It may contain no nitric nitrogen and being multi-purpose, there'll be a range of trace elements in there . . .

ScienceSquirrel - 11-6-2012 at 04:38

From the proportions NPK given in the review here I would guess that it is a mixture of potassium nitrate, and maybe ammonium phosphate or potassium phosphate. It is very quick acting so I suspect that it is nitrate heavy.
http://www.amazon.co.uk/Miracle-Gro-Purpose-Soluble-Plant-Fo...

The lawn food greens up grass in 3 - 5 days, I suspect loads of nitrate.

http://www.amazon.co.uk/Miracle-Gro-Water-Soluble-Lawn-Food/...

It should be easy to find out. Make a hot solution, filter and chill, big needle like crystals, potassium nitrate.

[Edited on 11-6-2012 by ScienceSquirrel]

MR AZIDE - 11-6-2012 at 10:44

Thanks for replies,


I will try the chilling of a solution of it. and see if any needles of KNO3 come out of it,
But seeing as how KNO3 isnt deliquescent, it may have KNO3 and loads of other other crap.

Even though the bag Ive been using, had been kept closed, the crystals are now very damp.



.....................


Ive just got hold of the container.........

NPK.....24-8-16

N total.........24%

Ammoniacal N.........3.5%
Ureic N.............20.5%

P2O5, soluble in ammonium citrate and water 8% ( 3.5%P)

K2O soluble in water 16% ( 13.3%K)

some trace element chelated EDTA


looks like there isnt any nitrate in it, BOOOOOOOOO!


DIT........

Ive just done a quick test, heating a small amount in a TT with solid NaOH.......mixture melted, has gone brown, and very strong NH3 released.




[Edited on 11-6-2012 by MR AZIDE]

CaptainOfSmug - 11-6-2012 at 14:16

I tried a quick experiment mixing the miracle grow with water, HCL then added copper pieces and aluminum to heat. I don' believe any nitrates were present. Only a clear gas was captured.

ScienceSquirrel - 12-6-2012 at 03:38

I was wrong.
Most of the nitrogen is urea

vmelkon - 12-6-2012 at 09:07

I had used a fertilizer from "plant-prod". It is a 500 g container and is marked 15-15-30 and this stuff does have KNO3. Blue crystals. The box says "Tomato, vegetable fertilizer" and from what I have read, tomatoes are nitrate hungry.
I can't tell you how much KNO3 it has exactly, but I used it to make nitric acid.

1. KNO3 + conc HCl + Cu -> NO

2. NO + O2 -> NO2

3. H2O + NO2 -> HNO2 + HNO3

[Edited on 12-6-2012 by vmelkon]

fledarmus - 13-6-2012 at 05:00

Miracle-gro 15-30-15 MSDS

Shows all of the major components

MR AZIDE - 13-6-2012 at 10:34

NICE find on the MSDS. I couldnt find it....

I made about 80 ml of a saturated solution of miracle gro, and the solution was deep blue, was cloudy, with a white precipitate.

Most of the precipitate was too fine to be able to filter using the filter paper.
The remaining undissolved crystals, were rinsed with water, which left behind small crystals, which on now looking at the DATA sheet, were the Boric acid.
Considering how much crystals I dissolved, It doesnt contain a lot of Boric acid.
The solution after being allowed to settle for a day, has deposited more of the precipitate leaving a clear blue solution.

If I cool the solution then some of the KCl might crystallize.