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miracle gro?

Posted by TheMasterGardener1 none (My Page) on
Mon, Oct 17, 11 at 23:16

Hello everyone.

I will be growing containers of greens (spinach and swiss chard) next spring. The mix will be peat/bark/perlite/lime. My question is, will 18-18-21 tomato mg fertilizer be ok for greens that require a higher N then PK ratio? Will the lime support all the the needed Ca, considering its missing in the micro nutrients of the fertilizer I am using? I noticed there is no sulfur in the micro either, is that needed?

Any help would be good. Thanks.


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RE: miracle gro?

I believe that fertilizer will be fine. the plants growth will only be restricted by the least available nutrient provided.
the lime will probably provide plenty of calcium. you could add some epsom salts for magnesium and sulfate.
Don't forget about iron. I know spinach supplies a lot of it and its got to come from somewhere.


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RE: miracle gro?

Hey thanks for the info. The only missing thing in the MG micro is sulfate, I could use the epsom to replace that.

Thanks again.


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RE: miracle gro?

Don't use soil fertilizer in hydro.

The main difference between hydro and soil fertilizers is the nitrogen source. Ideally, only calcium and potassium nitrate are used in hydro, where soil fertilizer often uses urea and ammonium based nitrogen. The urea requires a soil orgainsm that does not exist in a hydro system to convert to a usable product. The ammonium nitrogen can cause root damage if too much is used. It seems to work OK with up to 15% of the nitrogen source. Ammonia nitrogen can be used in moderate amounts to bring a high PH down.


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RE: miracle gro?

Hey thanks!!! I knew the urea took time to break down, i did not know that orgainsms where required to break down synthetic urea. I think I may just try somthing diffferent.


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