Bonsai Boy's Slow Release Bonsai Fertilizer Pellets-free Shipping with a BONSAI BOY Tree Purchase by Bonsai Boy. $2.95. Easy to use. 3 oz. packs. Just sprinkle 1/4 teaspoon of these slow release bonsai fertilizer pellets on top of the soil. Each time you water, the tree will receive nutrients. One application will last 3-6 months.4oz.