Woodace Tablets fertilize new plantings for up to 18 months. Formulated with IBDU Slow Release Nitrogen, each 17 gram tablet simulates a liquid injection site, with the advantage of less labor and longer feeding! IBDU Slow Release Nitrogen has a low salt content and nutrients are carried to roots in the soil solution. Unlike fertilizers that are blended into the backfill, tablets can provide essential nitrogen without burning delicate root hairs.