Deadheading, as Botanic Garden camellia and themes plant collection curator Marianne Groothuis explained, involved the removal of the dead flower heads, so ''the whole bush looks beautiful again''.
But, Ms Groothuis added, her husband was a Grateful Dead fan.
''Sometimes I get my husband to bring his guitar down, and he plays [Grateful] Dead songs for us while we deadhead''.
The deadheaders' picnic was a garden party she organised every year to thank the volunteers who helped deadhead the garden's blossoms.
''It's just my way of saying thank you to the ladies and gentlemen who help me deadhead the camellias during camellia season.''
And those volunteers, she said, were ''quite pleased to be referred to as the deadheaders''.
