Thieves have been "helping themselves" to immature produce from Blenheim's community garden for the past few months, an allotment organiser says.
Donald Oakes, president of the Riversdale Community House and organiser of the Community Edible Gardens, said the recent thefts meant new security measures would be put in place.
"These people, whoever they are, have no idea about gardening and are taking things that are immature," he said.
People were doing a good job growing food for themselves and the community and the thieves were wasting the gardeners' hard work, he said.
Chris Fortune, a member of the community garden trust, said it would be "disappointing" for people who had invested their time growing their produce to find it had been taken.
Water timers had also been ripped off the taps, ruining them.
The community garden would be fenced more securely, and police and community patrols were being considered, Mr Oakes said.
"We don't really want to start wielding the big stick; we want to get these people on our side and get them to see the benefits of working with us and helping rather than stealing ... because it's their community."
If the thieves needed the food, they could get in touch with the gardeners to arrange something, he said. "That's the general idea of the community gardens ... but we can't have people just coming in and helping themselves."
Mr Fortune said the trust welcomed anyone who wanted to use the gardens, but they had to respect what others were doing.
The allotment gardens are on land owned by the Nelson Marlborough Institute of Technology..
They are less than 12 months old and are rented by individuals and community groups who don't have the room to have vegetable gardens at their homes or premises.
The produce from the 12 allotments was eaten by those who held the allotments or given to the less fortunate by organisations such as John's Kitchen, Mr Oakes said. He urged anyone who saw people stealing from the allotment to get in touch with Riversdale Community House or the police.