A proven Phosphorous/Potassium boost for the flowering stage. used for only one week aprox 3 weeks from harvest.PK 13-14 is a dynamic flowering super-booster that will totally amaze you. It is an extremely concentrated formulation containing a carefully balanced and integrated blend of pure phosphorous and potassium elements for superior flowering results. This unique combination of elements can be called a super-bloomer that develops heavier, larger, sweeter crops extremely quickly. PK 13-14 has been proven by professional growers worldwide to increase the weight of your floral harvest significantly, crop after crop. Unlike substandard potash products, PK 13-14 has a guaranteed composition of 13% P205 and 14% K20. PK 13-14 is totally unique, absolutely safe, easy to use and incredibly effective. PK 13-14 is not a nutrient. It is a nutrient additive. A proven product that every grower should be using.