Greetings to all Jim. A liquid culture medium for pollen would be: To one liter of water. Calcium nitrate Ca (NO3) 2 300 milligrams (mgr) Magnesium nitrate Mg(NO3) 2 250 mgr Potassium nitrate KNO3 50 mgr Sugar 30 grams Take a small amount, add the pollen, at 6 hours look with a microscope, viable pollen there will be formed a polinic tube regards Fabio F