Pearson said she did not understand why plants grown for that show were more expensive than those grown for Hampton Court.
She added: "There are some good suppliers out there who have a lot of experience growing for Chelsea, but to get that you have to pay for it.
"I do think there are one or two growers that are charging a little bit too much compared to Hampton Court and that there's a premium for having plants at Chelsea. The same grower wouldn't charge the same for Hampton Court plants.
"I don't think it will put new designers off but I feel that young designers who have not done show gardens before might not know of the high cost involved."
Pearson aired her view on Twitter in response to HW's story (26 November) "Designers and growers start teaming up for Chelsea". She said: "I think growers charge too much for Chelsea plants."
Hardy's Cottage Garden Plants, which grows for both Chelsea and Hampton Court, owner Rosy Hardy responded: "Chelsea plants are always going to be more expensive because it's so out of season and you have to grow at least three times the amount of plant material to get the correct stock.
"When you are growing for Hampton Court you are much more in season and it's much easier. Obviously the grower is growing some material that they don't sell so they have to cover themselves."
She added: "It does take up a lot more time and effort to get the plants as the designers want them and sometimes it can be the designers' fault because they ask for material you cannot easily grow. Things like that have to be taken into consideration."