Does the fruit from trees, such as grapes and figs, which were planted during the life time of a person who is now deceased, benefit him in the Afterlife?
Is the one who waters them and takes care of them rewarded as well?
The fruit of such trees benefits them if they are Muslims, as the Prophet (peace be upon him) said,
There is no Muslim who plants a tree or sows seeds, and then an animal, a bird or a person eats from it, but is regarded as a reward of a Sadaqah (voluntary charity) for them.
It is hoped that the person who takes care of the plant will also have the same reward, as the bounty of Allah is great. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.