You can buy Currant grade Nika in online stores (seed and seedlings).
$16.01 Jobe’s Evergreen Fertilizer Spikes 13-3-4 Time Release Fertilizer for Juniper, Spruce, Cypress and All Other Evergreen Trees, 15 Spikes per Package
$134.99 Loropetalum Chinese Fringe Flower Plum Delight Qty 40 Live Flowering Plants
$24.99 Ross Root Feeder Economy Model #102A, For Use with Ross Fertilizer Refills (Ideal for Watering During Droughts), 1 Year Limited Warranty
$25.50 Transplant Formula - For Use With Plants and Seeds Including; Vegetables, Herbs, Fruit Trees, Shrubs, and Perennials - Great For Container and Raised Bed Gardens - Fine Powder Supplies Trace Minerals, Soil Microbes, and Biostimulant Carbons