Peter and Gardeners’ Question Time panel visit the historic Great Barn in Harmondsworth.

Beneath the medieval beams, Peter is joined by Bunny Guinness, Francis Tophill and James Wong as they tackle a wonderfully wide‑ranging set of questions from the audience that are as thought‑provoking as they are informative.

Are plants conscious? Why do camellia buds turn brown and drop? And which plants might humans take to grow on another planet?

Along the way, there’s practical advice on organic ways to keep vine weevils at bay, how to dry lilac flowers, and what to grow in pots in a narrow alleyway with limited light.

Later in the show Chris Beardshaw talks all things pruning - why, when and how.

Producer: Dan Cocker

A Somethin' Else production for BBC Radio 4

* If listening on BBC Sounds and you wish to view the plant list, please go to the Gardeners' Question Time website and open this week's episode page.