Urea 46-0-0 High Nitrogen Soil Supplement This bulk granular urea contains 46% nitrogen. It should be mixed into the soil or watered in immediately to avoid losing a percentage of that nitrogen content to the atmosphere in the form of ammonia gas, which can happen if the fertilizer is left on the surface of the soil. Highly soluble Can be applied to the soil or used as a foliar spray for certain plants Can be mixed with some other supplements , including sulphate of potash. Do not mix with superphosphate fertilizers I purchase Urea 46-0-0 in bulk. The soil Supplement is repacked in plastic zip lock bags.