HI
MOP- Potassium chloride is occasionally known as "muriate of potash," particularly when used as a fertilizer. t's odd how this old-fashioned name remains in use! Muriate comes from Muria, the Latin for brine. Muriate of potash is potassium chloride containing between 50 and 60 per cent potash. It was deposited eons ago by ancient seas and should be considered a natural product, blessed by organocultists, but it is not. Its chlorine content passes off rapidly when applied to soil.
As explained under soil organisms, however, muriate of potash is harmful to certain beneficial bacteria. Some authorities think sulfate of potash makes a better potash fertilizer.
SOP - Sulfate of Potash
This contains 48 per cent potash. It is more expensive than muriate of potash but is considered less harmful to bacteria and plant roots.Sulphate of Potash is virtually chloride free with a salt index of only 46 (whereas Muriate of Potash is 114). The essential sulphur content is in the readily plant available sulphate form. Sulphate of Potash consists of grey or white granules.
Providing potassium to crops sensitive to chloride and salt
Contains a low salt index helping to avoid the plant taking up excess water
Mixes well with all other fertiliser.
DEpending upon your soil ph , you can decide if you want to use SOP or MOP.
Regards
Ashwini