Staff and customers alike seemed in a positive mood, boosted by the sunshine.
Europlants managing director Renato Canale said: "The spring open days are always very good. We manage to get a lot of garden contractors, landscape architects and garden designers turning up. There are a few film people around too, which is good business for us. They always make big orders.
"It's been a mild winter and everyone seems to be upbeat about the new season. There's a lot of orders coming through. Yesterday we took quite a few orders and a number of substantial ones. There are signs of improvement in the market."
Canale said that sales had been improving since last year, moving towards the high of 2008 before the recession. But these sales are mainly landscape-related.
He added: "In retail it's still a bit tough but that's really down to the weather."
The open days were hosted by ITV's Love Your Garden presenter David Domoney. He said: "I think there's a great deal of confidence in the trade and not just in design and build. In garden centres there's a hope that we won't get any more bad weather before we get into spring."
National Trust Ickworth gardener Patrick McCormack said: "We've spent £2000 on plants this morning and we're going to buy more this afternoon too. We're looking at Cyprus trees and ferns for the new stumpery at Ickworth."
Sakura Gardens landscaper Jonathan Dowley said: "It's a great day here, and the fantastic weather helps. We're sourcing for a big job so we're planning on buying quite a lot of plants."
The company took delivery of a tonne of stock in six weeks in the run-up to the event.