Blackjak Overview Blackjak contains an astonishing 20% pure humic acid Blackjak is a concentrated suspension of humic, fulvic and ulmic acids plus exotic trace elements. Enhances quality and yield, naturally. Humic acid of this quality and concentration will have a direct beneficial impact on the physical, chemical and biological properties of soils, as well as a direct and positive influence on plants and crops. Adds fertility to soils and unleashes peak performance from plants. BLACKJAK is an aqueous liquid suspension of humic, fulvic and ulmic acids that is suitable for soil and foliar application. It can be used alone or mixed with a wide range of plant protection and plant nutrition products to optimize their performance. It enhances the formulation of sugar and starch and promotes root development in all crops.