The chemicals used in the sprays had specified withholding periods, typically 14 days but sometimes 28 days or even longer, during which fruit should not be eaten because it was likely to have chemical residue.
''You get really concerned. The people who take the fruit, and those who buy it, don't know when you've sprayed it.''
The culprits were generally youngsters who arrived on bicycles and filled their backpacks with as many avocados as they could reach.
The thefts had peaked in the second week of the school holidays.
She had heard about people approaching shop owners with boxes of avocados and last year kids had set up stalls on Kaikohe's main street.
There was a good reason why commercial growers had hazard signs at their gates, she said.
Ripping avocados roughly off the trees, instead of snipping them off with a piece of stem still attached, also exposed the fruit's flesh and made them vulnerable to rot.
John Dawson, Mid-North representative for the New Zealand Avocado Growers Association, said orchard thefts tended to occur in waves.
This season, avocados were not particularly expensive, because of a plentiful supply, so thefts were not a widespread problem.
With huge areas currently being planted in the Far North, it was unlikely New Zealanders would see a return to the high prices of a few years ago, and that would also make the kind of large scale-thefts seen in the past less likely.
While sprayed fruit had a withholding period before it could be sold for consumption, most of the spray remained on the fruit's skin. Imported fruit which was eaten skin and all was a greater concern when it came to spray residues, he said.
In 2019, shop prices for avocados hit $11 in some places, sparking thefts, prompting Mexican restaurants to cut back on guacamole, and fuelling the conversion of farmland into orchards.
In 2018, Kaikohe avocado grower Graeme Burgess lost 70 per cent of his crop to thieves, costing his business about $100,000.
The theft was pointless because the avocados were so far from maturity they would never ripen.
The thefts had occurred at night over a three-week period.
• Call police on 105 if you have information about orchard thefts or see any suspicious activity around orchards or elsewhere.