It is recommended to add EDDHA or completely replace your iron chelates with EDDHA (red iron) when the pH value is equal or greather than 6,5.
It is recommended to add EDDHA or completely replace your iron chelates with EDDHA (red iron) when the pH value is equal or greather than 6,5. EDDHA is stable till a very high pH. An EDDHA chelate with 6% iron and an ortho-ortho (O-O) of 4.8, means that the chelate contains 80% stable iron chelate. This doesn’t mean that the remaining 20% is not available for the plant at all, however, this will quickly precipitate and the uptake efficiency will be lower.
Chelated trace elements are more effective because the chelating molecules protect trace elements against insolubility and are also recognised by plant enzymes (that collect micronutrients and transport to tissues). There is a different chelating factor in pH target stability and light sensitivity.
You can also ask your question via the contact form. You will receive a response as soon as possible – even within 24 hours on working days.