Name: Kurt Woodbridge , Va (Zone 7a) Jai guru deva om
Magnesium sulfate , kind I think is what you want. I haven't heard of spraying plants with it , but watering or spreading a tablespoon on soil around plant before watering is suppose to help Magnesium hungry plant.
A pint can't hold a quart , If it is holding a pint it is doing the best that it can.
and it is written ,
if the evil spirit arms the tiger with claws , brahman provided wings for the dove.