The Dorset grower will supply camellias for display in the newly restored conservatory and offering varieties for sale. Trehane Nursery owner Jennifer Trehane will give a series of talks each Wednesday of the festival.
This is the second year that Trehane has supported the festival. The event takes place from 18 February to 18 March.
Trehane said camellias were popular and gardeners were getting better results from them than in the past. "People are getting more savvy about looking after them and modern varieties perform better," it added.