The 'barbecue brigade' want to liven up their patios with colourful flowers for entertaining guests in the summer, he explains.
Smith adds: "People buy plants in warmer weather and they can do that in June, July and August. Gardening has changed a bit. You don't see sales in the same numbers and it's obviously slowed up but there's more sales in those months than there used to be. There are less traditional gardeners around and people decorate their gardens for summer living and if they're entertaining and using the garden as an outdoor room they make it look good when friends are around."
The end of the peak box bedding season was traditionally on horse racing's Epsom Derby Day, which was on 3 June, while others believe that Wimbledon tennis fortnight, which starts on 3 July this year, signals the end of plant buying.
Newey Group’s Alex Newey says plant sales really slow down now when the school holidays begin in mid July and that bedding sales used to start in mid May, so a Derby Day finish would only give a two-week season.
He says, until mid July: "it’s open season, though by early June the peak is coming towards the end with the largest volume weeks over." But he adds: "The next weeks are important because, like any business, all the profit comes in the last weeks."
Newey says the season has been "OK — there’s always high points and low points in any one season. It’s how you deal with the low points." He adds that it will be "about the same as last year — sales of nursery stock have been good, sales of bedding not as strong".
Smith says the "classic" Derby Day end does still stand because sales have slowed at the start of June after a late May uplift capped a season that he says has been good overall, albeit "up and down" after a strong start and pause in the first three weeks of May.
Most gardeners have done their gardens because they have had enough good weather to do so, leaving less keen gardeners to give "a few more busy weeks yet".
Garden Centre Association (GCA) chief executive Iain Wylie says the south and Midlands had "miserable" weather at times in May, which impacted on early to mid May sales. But April GCA member outdoor plant sales were up by 33.22% on April 2016 and overall sales showed an average year-to-date increase of 11.07%.
Burston Nurseries managing director James Alcaraz says sales have been "very buoyant", with plants selling out until late frosts, which gave "breathing space to kick off again", which all shows demand for box bedding is still strong. Garden centres selling more added value and container plants now extends the season into August, he adds.
Longacres Garden Centre’s Michael Ainley reports that bedding plants have been one of the stand-out areas of the shop since late May after three weeks of poorer weather made demand grow. "In the last week we clawed back from May."
Neame Lea Nursery managing director David Ball says: "It's been a very good year. We are really seeing the benefit of the new facilities, especially on quality."
Buckingham Garden Centre’s Chris Day says: "Bedding is 4-5% up on last year and because of the early start to the bedding season in April there are shortages there and we're having to look around other suppliers to keep the momentum going."
Woodlark Nurseries managing director Colin Edwards adds: "Obviously, it was a great start for bedding in April but the first three weeks of May were cold and we lost the gains from April. We gear up for the first May bank holiday but Easter took most of the stock for that bank holiday and that led to a slight shortage, but we have caught up a bit now. There's never going to be over stocks because of the great start."
The financial background to what precedes this season is shown in Defra's new 2016 National Statistics: Agriculture in the UK report. It reports that production of plants and flowers was up 4.7% last year. "Within the pot plant sector, production estimates and unit values for most crops have remained stable. Production in poinsettia, New Guinea impatiens, begonia and chrysanthemum showed slight reductions, though pot rose production rose as demand has increased. The value of pot plant production in 2016 was £892m.
"The weakening pound against the euro and US dollar helped stabilise prices for both inputs and outputs. The average producer price of agricultural products fell slightly (0.5%) while the average price of agricultural inputs fell by 2.1%."