What is the nisab for zakat on vegetables designated for trade, and how is its percentage calculated (one-quarter of one-tenth, one-tenth, or one-fifth), given reliance on irrigation from wells? And is the nisab calculated on the whole amount or after distributing profits among partners?

Zakat is not obligatory on vegetables like potatoes and tomatoes unless they are sold. In that case, their price is subject to Zakat once it reaches the nisab (threshold) and a hawl (full lunar year) has passed.

However, if vegetables are stored in refrigerators with the intention of sale, and a hawl passes while they are stored, then Zakat on trade goods becomes obligatory. They are valued, and one-fourth of one-tenth (2.5%) of their value is given as Zakat.

It is a condition that the total amount of wealth reaches the nisab; the share of each partner is not considered individually. If the wealth is distributed among the partners before the hawl is completed, then the share of each partner is considered separately.