A Balanced Fish based fertilizer to be applied around the blackberry plant when they come out of dormancy and again when they start to flower. TOM DOYLE’S ORGANIC BLACKBERRY SPECIAL 4-4-4 Fertilizer Most of today’s garden soil is depleted of the natural organic matter that is in good top soil. My Blackberry Special contains nutrients derived from plants and animals (including fish and kelp) along with soft rock phosphate, sulfate of potash, and natural humates. This combination feeds both your plants and the many soil microorganisms which break down other nutrient sources and make them available to your plants DIRECTIONS: MIX 1/8 CUP INTO THE DIRT THAT’S GOING BACK INTO THE PLANTING HOLE. AFTER PLANTING, SPREAD AND INCORPORATE INTO THE SOIL AN ADDITIONAL 1/2 CUP WITHIN A SIX INCH DIAMETER CIRCLE AROUND THE PLANT. AFTER INITIAL PLANTING, FERTILIZE WITH 1/2 CUP IN THE SPRING AND AGAIN ABOUT 3 WEEKS AFTER FLOWERING STARTS.