Fertilize your outdoor jasmine plant four times during the year. Once will be right after its late-winter pruning. Three more feedings should be evenly spaced during the spring, summer, and fall months. A 10-30-10 fertilizer is recommended for jasmine flower production. Use a slow-release granular form and broadcast it evenly under the plant. For indoor plants, use a liquid fertilizer, diluted in water. Thoroughly water to saturate the plant’s soil. Then, slowly pour the fertilizer over the soil. Allow excess water or fertilizer to drain off.