Several speakers at the event dismissed local sourcing as irrelevant to customers, but Dobbies head of restaurants Costas Constaninou disagreed, saying that it brought a premium to prices, in a keynote on stage interview with Horticulture Week's Matthew Appleby.
He added that 7am-7pm opening, children's rainforest-style cafes with soft play and butterfly farms, waitress service and trumpeting that your product was special, home-made, baked in-store and fresh were points of difference that would drive the group's 34 centres. Dobbies' Edinburgh centre is due to have a 'coffee to go' early morning entrance-way offer opening in the next few weeks.
Trendy offers such as small tapas plates were not a success at his former role at Wyevale, so traditional food was the way forward.
Pricing, he said, could be improved by improving specification, with line-caught cod replacing frozen fish at 15% higher prices: "We can be braver and charge more."
"There are few concepts out the in retail-land cooking British food and doing a good job. There is no banding."
Consultant Neville Stein said higher prices went "straight on the bottom line" but some delegates warned that food service product prices to garden centres needed watching as they were increasing faster than retail prices.
Klondyke Garden Centre's chief executive David Yardley said in planning revamps of Klondyke's 22 restaurants, they looked at queue management, improving food offer, customer service and call to order/waitress service, plus kitchen layout and equipment.
Getting return on capital through using a design that "works for us" was his message: "We're not saying what we do is the best but it works for us. No catering offer is wrong if you target the marjet you want to attract."
Garforth in West Yorkshire is the example others in the group are working from. Carlisle and Wilmslow have recently been refurbished.
Yardley said there had been a decline in diners sitting outside so air-con noise control through part false ceilings that traps noise were important. Yardley added that Trip Advisor reviews could be misleading because vocal competition could post negative reviews.
Salim Sajid of Rosebourne Garden Centre in Hampshire said the centre, built in 2016, had seen delays because of BREEAM and other environmental legislation, which he said "adds a huge amount to the development costs but the customer doesn't get a huge amount".
Sajid said table service gave a point of difference over the high street and online. But he warned delegates not to start with a "margin mindset" and urged them to put customer experience first. "Invest in waste", maintain quality, and sales will grow he said.
However, the value of garden centres' food offering was often restricted by owners' own ideas on how much food is worth, not what customers will pay, he suggested.
Rosebourne garden centre's food turnover could reach £3m Sajid said.
Stein and Coolings Dwayne Ross spoke about wages versus food costs, which they agreed was a balancing act between "very low food cost equals high wage costs or very low wage costs equals high food costs". Ross said upping prices had not harmed sales. He said savings on food costs could be made through portion control by serving peas in small bowls for instance, as well as vac-packing leftover Sunday roasts for sale the following week.
A 21% food cost, 37% wage cost and 40% net profit was suggested.
Meanwhile, Compass Group's Russ Scanlon said a successful partnership with Garsons in Esher had shown myths about outsourcing companies being "wolves in sheep's clothing" were unfounded.