Is zakat due on three plots of land—one for immediate construction and two for future benefit (sale or development)—after six years have passed without its zakat being paid, and what is the amount of zakat due?

"Lands purchased by an individual do not fall outside of three categories:

1. That which is intended for residential use: There is no zakat on it because it is not for commercial purposes.

2. That which is purchased with the intention of trade and seeking profit: These are trade goods, to be appraised at the completion of a year (hawl), and one-quarter of one-tenth (2.5%) of their value is to be given as zakat.

3. That which is intended for investment (building shops or apartment buildings for rent): There is no zakat on its principal, but rather the zakat is on its yield if it reaches the minimum threshold (nisab) and a year (hawl) passes on it from the time the lease contract is concluded."