Our rapeseed is an organic fertilizer for plants.  Maruta brand is manufactured in Japan and contains no animal products, including bonemeal. Nearly impossible to overfeed, as it is long-lasting. Replace every 50 days in summer and 100 days in winter. Each cake is approximately 1.0" x 1.0" in diameter. Apply 1 or 2 cakes for average size container. Will not deteriorate. Free shipping with tree order.