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Name: Albert D.
Status: other
Age: 60s
Location: N/A
Country: N/A
Date: 2001-2002

the glasshouse to growing tomatoes organically. At present the whole nursery is under hydroponics with a complete nutritional feed formula that includes magnesium sulphate for supplying magnesium to the plants which they need in fairly high quantities for high production. This will not be permitted under the rules for growing organically but if the raw material from which MgSO4 is extracted does not contain material which is deleterious to the plants then this crude material may be used. It will be less potent but will nevertheless supply the element required. Do you know the contents of the crude material and even where it is "mined" these days. It used to be in the Epsom area of England hence it's common name of Epsom salts. An answer to this query will be greatly appreciated.

Not being familiar with the "organic growing" rule book, I can't comment specifically; however, magnesium is available in many "naturally-occurring" minerals. The web site is a definitive reference regarding these mineral sources of magnesium.

Vince Calder

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