Industry figures have responded by highlighting the high quality and value for money that many wholesalers supplying supermarkets achieve - and the role they play in bringing in new gardeners.
Speaking to Radio 4’s You and Yours programme, to be broadcast on 5 June, Don said the ranges of plants for sale were not big enough for him: "You have these vast wholesale nurseries now supplying supermarkets and actually that's a diminution of choice that's bad, because all you get it’s rather like vast suppliers supplying food. You get lots and lots of exactly the same thing, mass produced to be as cheap as possible."
Don says he would rather use small independent growers to talk to plant experts: "I'm a huge a fan of independent nurseries and that is where you get the expertise that is where you will find people who have devoted their life's to growing something and know far more about it than I do or anyone else on television, because their life on one thing, so they will grow you know geraniums or they will grow fruit trees whatever and they will really know about it. So when you contact them, they can...they can give you great hope and assistance."
Garden writer Peter Seabrook said, that plants including geraniums from Kado Flowers, who supply Waitrose, and lilies from Pinetops Nurseries on his 40 Sunbury Rd RHS Chelsea Flower Show exhibit were of "unbelievable quality" and represented good value for ordinary as well as dedicated gardeners.
"The large production nurseries growing for supermarkets are producing an unbelievable quality that 20 years ago I wouldn't have dreamed of and all offer remarkable value to new homeowners and very keen gardeners alike."
Garden Centre Association chief executive Iain Wylie said: "Everyone has a different model. Specialist food outlets might retail more types of jam and more quirky goods than the supermarket. One independent garden centre is different to the next independent garden centre, which is different to Wyevale Garden Centres and different to Homebase or a supermarket. Supermarket's bread and butter is working in volume.
"In my parents' generation everyone bought roses from Woolworth's. They got their first house and planted them and then moved on the find their local nurseries and garden centres once they gained confidence and expanded their gardening. Garden centres and nurseries aren't going to be the only places selling plants and if supermarkets generate interest in gardening that's got to be a good thing for independent garden centres, bigger garden centres and independent and wholesale growers. It's all about adding value to our industry."
Greg Hill, British Protected Ornamentals Association chairman and director of Hills Plants, which supplies Sainsbury’s, Waitrose, Marks and Spencer and Homebase with pot plants, said: "We started out as a small independent nursery with a retail outlet and I believe we are still as passionate about plants now as we were then."
Martin Simmons, HTA director of operations, said: "People often make impulse purchases of plants in supermarkets and if this then encourages them to buy more plants then this is good for the industry and helps to grow the market.
"Buying a plant in a supermarket may be the first step for some consumers, particularly younger ones. If this grabs their interest they will naturally seek out garden centres and retail nurseries."
Kantar said nearly 40% of gardeners buy plants, bulbs and seeds from supermarkets.
Don has also admitted that he did not watch Gardener's World when he was younger and did not even like the 50-year old show, where he has been lead presenter from 2003-08 and since 2011: "When I was a child I have no memory of watching it at all. I knew who Percy Thrower was. He was a famous figure and I knew that he was a gardener, but I don't remember ever watching 'Gardeners World' before I was in my 20s.
"And then I started to watch it because I by then was gardening a lot. I'd, well I'd always gardened as a child and I decided to make my own garden. Watch 'Gardeners World' and I have said this before, but it and it sounds disloyal, but I didn't like it! I didn't l like 'Gardeners World' I didn't like any gardening on television at all because I was 25/26 and it seemed to me something for middle-aged people. And this was in the early 80s and I didn't know many other people with gardens. In other words, I wasn't part of a gardening community really in anyway; it was just me and Sarah making a garden. And it took me a few years to appreciate 'Gardeners World' you know I just thought I'm young, I'm doing my thing and these are all middle-aged people in cardigans and they're not speaking to me."
Don nominated bedding plants as the most influential plant during the 50 years if the show, but says: "It wasn't my favourite plant, it was the plant I think has changed gardening most because people can go to the garden centre, buy a tray of bedding plants plant them out."
Last year Don was criticised for saying begonias were "repulsive" during a BBC Chelsea Flower Show broadcast.
The plant he says every garden should have is a rose, specifically Cuisse de Nymphe’, Alba semi plena, or Alba maxima.
He says the biggest impact on gardening in the last 50 years has car ownership allowing gardeners to pick up plants from garden centres, which he says "changed everything". The third big change has been Sunday trading which "meant was people could drive to a garden centre, put plants in the boot, take them home and plant them. Now that's number one".