The group has also planted verbena, foxgloves, strawberries, sunflowers, geraniums, and sweet peas outside the bunker.
Plot holder Catharine Braithwaite said the shelter is an important part of the heritage of the area and the rest of the country.
She said their work won’t stop there, with more plans to help the allotment adapt to the impact of climate change.
“We’ve got nearly £2,000 from the National Lottery to do a bog garden, more wildlife habitat and water harvesting, so it’s really amazing to get that money.”