In article ,
Mike Lyle wrote:

[ Urea ]

Returning, however, to our muttons, I Wikipeed, and found that
applications normally varied from 40 to 300 kg per ha, and it's "not
compatible with other fertilisers". So clearly some technical knowledge
is required here!

I believe that that mainly means ammonium nitrate, though God alone
knows why you would want to mix two nitrogenous fertilisers ....


Regards,
Nick Maclaren.