Popular family attraction Windermere Berry Farm has cancelled pick-your-own days after repeated thefts and other poor behaviour.

For the second year in a row, staff have been forced to put a temporary stop to the farm's pick-your-own strawberry service.

Yesterday, people who had paid for the experience were seen wrenching a waratah out of the ground and picking strawberries from a block that was off-limits.

Cafe manager at Windermere Berry Farm, Matthew Boswell, posted the news of the closure on Facebook yesterday and more than 70 disappointed customers commented on it.

"We made an exception for one family because they'd come up from Wellington. It was a large family and they'd hired a van to come here and do this," Boswell said.

"However, for a large number of other people, it's a trip they planned and now it can't be done and that sucks."

There was more than one reason for the closure, with more berries being taken than were paid for on numerous occasions.

"We've had people picking strawberries, putting them in icecream containers, taking them to their cars, empyting them, then going back and refilling them too," Boswell said.

"It's been pretty bad. If we're selling 120 experiences and 20 are stealing, say they've stolen 20 kilograms of strawberries in one day, that's quite major."

Boswell estimated - through the records that they keep and the money in the till - that the farm had lost 60kg of strawberries, valued at $600.

He was quick to point out that the closure is temporary while staff consider their options of how to operate going forward.

Some possibilities are that PYO becomes a weekend experience that only opens up blocks near the office, where a member of staff will be able to observe the pickers in action.

"I'm trying to make this experience work, everyone around Whanganui knows that Windermere is an experience for people that live here and people passing through.

"The fact that I've got to stop that now and might only be able to bring it back on weekends, that is ruining the experience I want to provide for anyone who comes here."

Windermere has been a berry farm for more than 50 years and was purchased by the Boswell family in 2011.

Open seven days a week, it has a cafe on site and a store that sells honey, jam, wine and of course, berries.

Boswell hoped people would get behind it when pick-your-own was made available again by following the rules and confront anyone who flouted those rules.