Around 100,000 people are on waiting lists in the UK while allotment numbers fell from 1.4 million in 1945 to 300,000 in 1997.
Presenter Joe Swift, who is the programme's allotment gardener, said: "The campaign is likely to be a strand in Gardeners' World. There are lots of meetings going on in the hierarchy at the moment.
"We will highlight a law that says if enough people pressure a council to create plots, it is obliged to investigate." Relevant laws are the Allotment Act 1887, which obliges local authorities to provide allotments if there is a demand for them, and the Small Holdings & Allotments Act 1908, which consolidated impositions for parish, urban district and borough councils to provide allotments.
The new series begins today (3 April) and will feature Swift's London allotment. He said more allotments must be created. "There's a huge demand. In Hackney and Islington there's a massive waiting list. The issue is the same old one - lack of green space.
"My whole site is full for the first time in years. It's so fantastic. There's a lot of newcomers. The great thing is there is a lot of information, knowledge and community spirit. I can't see any negative sides to it.
"People value growing spaces for health and educational benefits. I hope this is no flash in the pan and everyone keeps growing."