This year's plant fair sees the return of many familiar faces as well as new exhibitors, including Iris of Sissinghurst.
Striking auriculas, scrambling clematis and historic dianthus are amongst the wide range of beautiful and unusual plants that will be sold on the day.
Historic garden tools will also be on sale, and for the first time at this event, Holly Antrum will run an art workshop for children and families.
The new organic cafe will serve food, and visitors will also be able to enjoy the delights of the knot garden filled with tulips.
Plant fair visitors will also see the museum's newly sown and planted wild garden, developed in response to the growing awareness of the need for greater bio-diversity within urban areas.