A South African couple living near Nelson were stunned to discover racial slurs tagged all over their property in red paint.

The couple, who wish to remain anonymous, had just sold their home in Richmond when they found the words "Sth African C***s" painted in bright red on their driveway and fence last weekend.

"On Sunday morning I woke up, just like a normal day and had coffee outside with my dog when I noticed there was spray paint all over the fence the mail box and the driveway," the male homeowner told the Herald.

The overnight incident has shocked the couple, who moved to New Zealand in 2016 to escape racist beliefs.

"Racism is quite rife in South Africa and it's probably the main reason we left," he said.

"We never had anything like this in SA and then you move to a first world country ... now we are a victim of racism and vandalism all in one. It's not very comforting."

The man spent hours painting the driveway and trying to remove the red words on his property.

He wasn't able to get the racial slurs off the fence and he is concerned about replacing it in case they are targeted again before the new homeowners move in next month.

"I don't want to be paying for a fence twice."

However, he will replace it once they move out.

A neighbour posted on the Facebook community page Nelson Snippets seeking any advice on the incident to help the couple find the culprit.

One person said it must have happened before 10.30pm as their daughter arrived home and saw it at that time. However, the neighbour was sure it was not there at 8.30pm when they arrived home themselves.

Another commented their concern for the couple saying: "I feel for the family who has had this happen to them, absolutely disgusting."

A good friend of the couple, who is also South African and lives nearby in Hope, said she was very hurt by the incident.

"People just see us as immigrants they don't always understand how much we had to sacrifice for our kids to have a better future."

The couple have reported the incident to police. Police told the Herald they are aware of the incident and are investigating.