Dobbies has 25 centres and wants 75 more by 2018. Fife-based hardy plant supplier and distributor Growforth owner Stan Green said: "It is very difficult for smaller, more specialist Scottish horticultural producers to keep up with that level of supply. A lot of people in the past two or three years have decided that scale of operation is not for them and by mutual agreement have decided to move on. My worry is longer-term."
Green added that the garden centre market in Scotland was increasingly split between small, local plant nurseries and large, £5m turnover destination centres that make 40 per cent of turnover from catering.
However, he admitted that chains and sheds brought people into gardening and, as they became more interested, they shopped at more specialist outlets
Glendoick Garden Centre managing director Ken Cox said: "The big issue facing Scottish horticulture seems to be Dobbies. Before Tesco bought Dobbies, it used to source plants in Scotland and via Scottish distributors. As far as I can gather, that is going."
However, Neil Fishlock, head of horticulture at Dobbies, which sources soft fruit plants from Moyness Nurseries in Perthshire as well as heathers from Scottish grower Highland Heathers, said local sourcing was extremely important to Dobbies.
"Our sourcing policy is to find products that offer the best quality and value for money. Local sourcing is extremely important to Dobbies and is guided by our environmental policy, which aims to continually raise the practice of energy conservation, sustainable sourcing and recycling across the business."
He added: "There is a very good supply chain in Scotland, which makes our ability to source from the most appropriate suppliers practical. For a purely practical reason, a proportion of our plant stock will come from south of the border, where light levels and temperatures are a little higher."