She says she burst into tears when she found it was now "ruined" by bloodstains, dirty smudges, a torn trail, and large safety pins leaving holes.
"I just bawled my eyes out," Ms Harkess said.
"It's my actual dream dress. This was my worst nightmare."
Ian Harper, owner of Sharp Image Drycleaners, which contracts to a Christchurch drycleaning firm, denies the dress was damaged in the cleaning process.
Mr Harper says he's spoken with the two drycleaners who handled the dress and they remembered it as "quite difficult but they managed it okay".
They never use safety pins, he said. Any marks, including bloodstains, must have been pre-existing, Mr Harper says.
He says in 13 years of business he's never had complaints with the handling of wedding dresses.
Consumer New Zealand chief executive Suzanne Chetwin said many drycleaners had customers sign a waiver or disclaimer.
Ms Harkess has rights under the Consumer Guarantees Act, Ms Chetwin said, and could lodge a claim with the Disputes Tribunal.
The consumer advocate hoped the drycleaning firm would "learn some lessons" from the complaint.
Mr Harper says the incident has led him to change how he operates.
"I'll be pretty careful in inspecting dresses before and after they are cleaned," he said.
He has offered to refund Ms Harkess the $140 drycleaning fee, but refuses to pay for the Canterbury tailor mending it for the November 13 wedding.
Ms Harkess says she is trying not to let her big day be ruined.
"I know that, no matter what, my day will be perfect because I will be marrying my best friend," she said.
"But I am just so upset that this has happened. It's a bride's worst nightmare."
