BD #501 should be used only after BD #500 has been used. It stimulates photosynthesis and the ripening process, regulates leaf growth, enhances flavor and storage quality. BD #501(F) is a a Feldspar-based form of Horn Silica recommended for sandy soils.
How to use BD #501 Stir vigorously for one hour in sufficient water to meet your application requirements. Apply immediately to foliage. Apply periodically during the growing season. One unit is enough for once acre when stirred properly. Tip: Spray in early morning before the heat of the day.
Warning: DO NOT APPLY TO PLANTS WHILE THE FLOWERS ARE OPEN.