It's this type of bartering arrangement - along with producing fruit, vegetables and eggs from their own garden - that Lydia believes will sustain her, her husband Matt and their four children during a year of spending no money on food.
Lydia admits it's a crazy idea, and most of her friends think she'll never be able to do it.
Lydia and Matt began to think seriously about their lifestyle when their youngest child, Ashton, was diagnosed with celiac disease - an allergy to gluten - and dairy intolerance at the age of three.
"We didn't really know anything about food then. We thought we were healthy eaters. But Ashton was getting sicker and sicker. We didn't know what to do," Lydia says.
"But one night we took him to A&E and the doctor there said, 'Cut gluten and dairy out of his diet. I'd put my money on that being your son's problem.' So we did, and within a month he was well again."
This diagnosis prompted Lydia to start thinking about the food her family was eating.
"I started wondering why our food was making him sick. And then I started asking questions - reading all the ingredients on packets and googling anything that I didn't understand. I realised that so much of what we eat isn't even proper food."
Lydia's focus now is on locally sourced, unprocessed food. She began gardening, growing vegetables and adding more fruit trees to the family's Gonville property, and rescuing battery hens to provide eggs.
"I'm not super strict with my kids. We go to barbecues and parties, and that's their time to indulge if they want. But when we're at home we eat locally sourced and homemade food."
For the past couple of years Lydia has been slowly whittling away at her food bill, finding ever more creative ways to provide food, in preparation for the zero dollars spend in 2017.
The idea of spending no money on food for a year began when Lydia realised that the wages from her job in hospitality just covered the family's food bill.
"We were struggling financially, especially after my son was sick. And we looked at how we could make savings, and we found that apart from the mortgage our biggest bill was food. Growing kids eat a lot of food," Lydia says.
"Every laughed at us and told us we couldn't cut back on food because it's a necessity. But we're not cutting back on it - just not spending money on it. It's not unusual for people with five or six people in their family to spend $400 or more a week on food.
And I thought, why am I working just to buy food for my family, when I don't need to?"
While most families would be heading off to the supermarket to pick up their groceries, Lydia begins by making friends. She is a big believer in the power of community.
"My motto is that if you give freely, it will come back to you freely. We always have so much surplus, and we give what we have - fruit, vegetables, eggs, baking - and although we don't ask for anything in return, people are happy to give back to us."
Lydia and Matt realised their property - while very productive for an ordinary suburban garden - would not be enough to sustain them, so Lydia started looking for other sources of food that didn't cost money.
A chance meeting with a Westmere family ended with Lydia offering to look after their overgrown orchard and large glasshouses - which the family had planned to get rid of - in exchange for some of the produce from the garden.
"And then through them we met a wonderful woman up the Whanganui River who needed some gardening help, and she has a whole different kind of orchard with things like avocados. I've also just met a nurse in Fordell who wants a garden but doesn't have the time to do it, so I'm going to work for her in exchange for half of her vegetables."
A keen baker, Lydia gives baking away to various friends and acquaintances and, although she doesn't ask for it, she receives baking ingredients in return - things she can't grow herself, such as flour, salt, sugar, spices and other pantry items. She also does housework in exchange for home-kill meat.
Currently the family grocery bill is less than $200 a fortnight, but Lydia has plans to shave even more off that.
"There are some things that we're still working on. My kids love farm milk, and a friend of a friend produces raw milk and will do trades for it. So we should have our milk sorted. And I know someone who does cheese-making so I'm hoping to learn how to make cheese.
"Finding a source for almond milk is something I'm still working on, because we do drink a lot of almond milk, especially as our youngest can't have dairy."
And Lydia has told everyone what she wants for her birthday: "Whittaker's dark chocolate! Anything else I can just about do without."
At first her husband was doubtful whether spending no money on food could be done, but Lydia said he's now "keen" and is always thinking of ideas to make it happen.
"The kids are fine about it. As long as they have food on the table, they don't really mind. One of my boys - he's the only one who's in school at the moment - he trades his homemade lunch with someone who has a bought lunch. And that's fine, if that's what he wants to do."
Lydia admits that what she and her family are doing is not for everyone. She said it has taken a lot of organising and planning to make sure it will work.
"I don't think we could do it if [Matt and I] were both working full-time. I cook everything from scratch, and if I was at work I just wouldn't be bothered with that.
"I like being able to spend my weekends with my family, and being able to provide good food for my family, rather than having to be at work."
