Thread: сажать, садить, пересажать, пересадить

My understanding is that сажать means "to plant" as in putting a plant or seeds into the ground. It is also my understanding that садить is a colloquial form of сажать. So, is it the case that пересажать means "to transplant" and that пересадить is a colloquial form of that word?

When used without prefixes, cажать and садить differ only stylistically. But when used with prefixes, they actually differ in their meanings:

пересадить - here пере- means trans-, inter-
1) to transplant
2) to replant
imperfective: пересаживать

пересажать - here пере- means "over and over",
1) to plant (several objects) one after other in sequence; to plant all of (several objects)
2) to jail (several persons) in sequence; to jail all of (several persons)
no imperfective

пересажать can be further supplemented with the emphasis prefix по- (попересажать), having the meaning of an
instant, sudden and/or inevitable action.

1) пересажать means "посадить всё/всех". Could refer to plants or criminals.
Compare to: переловить, пересчитать, перечислить, перебить, ...

2) transplant - пересаживать. Пересадить - perfective form.
Compare to: переводить, переезжать, перемещать, ...

2 different shades of meaning for пере- so to speak.

Пересажать/пересадить with the meaning of jailing a group of people can also imply negative connotation of doing so illegally, typically for the purpose of getting rid of those people.

"Этот новый политический лидер начал с того что пересажал всех своих противников" ~ "This new political leader started off by putting all of his opponents behind the bars." (to get rid of them)