How is zakat calculated for agricultural land that has been converted for selling trees and saplings, considering the existence of costs and expenses for workers, and the death and damage of trees, bearing in mind that the land does not belong to the questioner but to his father?

If trees and seeds are purchased for planting and sale (as a trade), zakat is due on them as trade goods, by appraising their value at the end of the year, adding any cash one possesses, and giving out a quarter of a tenth (2.5%) if the amount reaches the nisab.

However, if trees are grown for sale without being purchased for the purpose of trade, no zakat is due on them until they are sold, and their proceeds are then subject to zakat if a year passes over them and they reach the nisab.

If the trees produce fruits on which zakat is obligatory, such as dates and olives, then the zakat on fruits is due at harvest time (one-tenth if irrigated without cost, and half a tenth if irrigated with cost), provided they reach the nisab (approximately 612 kg). As for fruits, there is no zakat on them according to the most authoritative opinion.