I socialise with the Manager of a local garden centre chain. According to him the big spenders in garden centres are couples in their early 50s. The garden centres sell the upmarket stuff whilst the DIY shops sell the tat.Sad. The Clyde Valley here used to be full of tomato growers (decades ago). The product was excellent, albeit with a short season. An ex-grower told me it was the cost of energy that put them out of business and makes a return unlikely. The previous small-holdings are all garden-centres now. Full of white haired old farts buying patio tat and pest-control products.
Also "white haired old farts" tend to spend their money on bird feeding stuff after treating themselves to a cheap lunch in the garden cafe.