The Tesco-owned garden centre chain is believed to be having difficulties in winning planning permission from Carlisle City Council, which has recently turned down an application from Tesco to build a supermarket in the city.
A park-and-ride service on site could be seen as a way to win permission, according to insiders.
Motorists would leave their cars at the park-and-ride facility and catch a Stagecoach service bus into Carlisle city centre.
Martlew said that such a scheme would be far cheaper than Cumbria County Council's proposals for a park-and-ride at Morton.
He added: "I have suggested this idea to Dobbies and they seem quite keen, and the bus company is reasonably receptive."
Dobbies hopes to open its garden centre by March 2010 but has yet to receive planning permission.
Martlew's suggestion is that the company would be required to provide a park-and-ride car park as a condition of planning consent.
Dobbies' director of property and development, Stuart Wright, has written to the Labour MP offering talks on the idea.
His letter said: "We would welcome the opportunity to discuss such a facility as I can see that there could be some benefits for all parties concerned. We do have additional land within our ownership out with the application site and it may be that this could come into play."
Klondyke opened a destination centre near Carlisle in 2006.
Meanwhile, Dobbies' plans for new builds in York and East Kilbride have been delayed. The East Kilbride proposal has been recommended for refusal but is yet to go to the planning committee.
A Dobbies representative said: "There is no update on these developments yet."