What type of fertilizer releases nutrients over a long period of time?

Slow release fertilizers are designed to gradually supply nutrients to plants over an extended period. This slow release mechanism is beneficial for maintaining a stable nutrient supply, minimizing nutrient leaching, and reducing the frequency of fertilizer applications. The nutrients are typically encapsulated in a resin or coated in a way that controls the rate of release based on factors such as soil temperature and moisture.

Special purpose fertilizers are tailored for specific plant needs or growth stages but do not necessarily focus on nutrient release duration. Incomplete fertilizers contain only certain essential nutrients while lacking others, which does not define their release characteristics. Complete fertilizers provide all essential nutrients in adequate amounts but may not have the slow release properties that manage nutrient availability over time.

Therefore, among the options, slow release fertilizers best characterize those that release nutrients consistently over a prolonged period, supporting plant health and growth more effectively.