He said Windermere had always struggled on three fronts - weather, staff and markets.
However, its fantastic soil was an asset and water was ample. This season had been marred by the weather as more sun was needed to ripen berries and to get people out and in a buying mood.
Christmas had been a tough time. The gardens only had second-year berry plants because it had been in difficulties at planting time last year. When torrential rain fell in the week before Christmas, the plants became dormant and there was not enough fruit. Traditional customers were upset and Mr Walker was, too.
"It turns you inside out, it really does, because you get factors beyond your control a lot of the time," he said.
He has now put new measures in place such as a website, Windermeregardens.co.nz and started growing blackberries with success - the bumper crop this year has sold well.
Jam made from Windermere berries is made on the premises and there is honey too - from hives brought in to pollinate the plants.
Mr Walker has developed new packaging for the free-flow frozen berries, which are now sold in New World supermarkets and gourmet groceries.
Windermere's cafe sells berry icecreams, wines and liqueur, and also stocks other gourmet and specialty food lines.
Windermere berries are sold at Wanganui's market and in Feilding and Palmerston North, and the business also supplies big events such as weddings and the Waimarino Rodeo.
Mr Walker's daily task is to find the best possible markets for the berries that pour in.
The gardens currently have about 30 workers but in summer they can employ up to 150 people - 100 pickers, 25 packers and 15 in the store and cafe.
There's never a shortage of unemployed people to hire, but finding ones who will turn up in any weather and work hard is one of the challenges, he says.
By midwinter, staff numbers will be down to about six and the cafe will probably close.
But there's no rest even then - that's the time when Mr Walker plans to plant a big first-year strawberry crop, more raspberries and blueberries.