He thoroughly dug it, removed its stones,
and planted it with the choicest vines.
He built a watchtower in the midst of it,
and also hewed out a winepress in it.
He looked for it to yield grapes,
but it yielded wild grapes. Bible

“watchtower.” To protect the crops from pests and thieves it was the custom to build temporary booths or more permanent watchtowers in the fields. This was one of the more permanent watchtowers. [For more on booths and watchtowers, see commentary on Isa. 1:8].

Commentary for: Isaiah 5:2