There have also been enquiries from people planning trips to Antarctica.
The boots are stocked by 75 stores nationwide, including Hunting & Fishing New Zealand and at Palmers Garden Centres.
The Sheaffs had owned local retail store Hula for 10 years but sold it 18 months ago as the wholesale side of Boonies rocketed.
"We were getting busier and busier and Glen needed support, so it was a no-brainer," Julia says.
The Northland Field Days start this month, and the Sheaffs credit part of their success to meeting customers face-to-face at such agriculture events. "Being able to respond to what the market needs quickly is a huge advantage for us. We get feedback from the field days and act on that."
Another Tauranga company that values field days and expos is Kliptank, which has increased its business by 300 per cent year on year since starting three years ago.
It manufactures above-ground bulk storage tanks for water and dairy farm effluent - a system invented by its director, Neil Peterken.
North Island sales manager David Parker says growth has been huge and they have moved to a purpose-built 3000sq m building at Tauriko.
"Business is wonderful and we are really starting to get traction now," Parker says.
Kliptank employs 10 staff and makes about 50 tanks a year. Field days and expos have been important to showcase new products and generate awareness, he says.
"The field days are a great focal point for the North and we need to be there."
Northland Field Days president Lew Duggan says Bay of Plenty exhibitors are extremely important to the event.
"This is Northland's largest ag event and provides an opportunity for the public to find out about wider opportunities with national businesses' offerings."
The number of Australian companies represented has doubled this year with 50 new exhibitors registered.