The film follows her through the historic town as she passes landmarks and local businesses, collecting picnic items in her basket from the town's shopkeepers.
The red bicycle, which appears to be peddling along by itself, was actually ridden by Mr Blackwell wearing a full-body green Lycra suit.
In post-production, the fully green Mr Blackwell was removed from the video using green-screen techniques.
He said the film had not been made "on a shoe string" but had been produced on a "really cost-effective" budget.
"We couldn't have really done it without the goodwill of the local retailers.
"They all thought it was a nice story to be told about Greytown and it was done in a really unique way."
The video can be found on the website of Blackwell and Sons, which opened on Main St in September last year at www.blackwellandsons.nz.