Grotek� Blossom Blaster� is a concentrated formula for early flower development and provides available phosphorous to improve root development and aid in blooming and fruiting. Potassium is instrumental in moving sugars produced by photosynthesis. This powerful flowering supplement should be added twice during the initial 3 weeks of flowering. Grotek� Blossom Blaster� is effective in all growing mediums and is compatible with all base nutrients. Do not use as a foliar spray. Always use fresh product. Do not add to existing solutions.