There is no due Zakah on the vegetables. Only when you sell some vegetables and receive cash and a full lunar year passes after earning this money, you should then pay the due Zakah if it reaches the Nisab (the minimum amount on which Zakah is due) separately or when added to other money earned by the same owner. (Part No. 8; Page No. 20)
As for the palm trees, when the harvest reaches the Nisab, which is 300 Sa` according to the Prophet's Sa` that is equal to approximately 3 kilograms , you must pay 10% thereof if irrigation is natural and incurs no cost ; however, when irrigation is mechanical and incurs costs, then only 5% should be paid. If you sell the harvest, you should give the value of the amount mentioned, which is 5% or 10%.
The commodities sold at the grocery store should be estimated after a full lunar year passes from the time of buying them, then only the commodities prepared for sale should be evaluated according to their price at the end of the year and 2.5% of their value should be given as Zakah.
Only 2.5% should be paid as the Zakah on the money saved from salaries and the store value after a lunar year passes while they are a Nisab [or more].May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.