Propagation volunteer Chris Mills said salvias are always popular and grow well in the Orange climate and they were a good flowering plant that attracts bees and birds.

Among the threatened species he said would be sold was prostanthera, a plant that only grows on Mt Canobolas.

Mr Mills said the prostanthera on the mountain are recovering from last year's bush fire but by propagating and selling the plants domestically it would increase its chance of survival.

Proceeds would go to the projects FOBG undertakes within the gardens such as work on a new native garden and upgrading the irrigation system.

"Please bring something to take your plants home in. We will have some boxes but we run out," Mr Mills said.

The sale will take place at the Orange Botanic Garden between 8am and noon and Mr Mills recommends people get there early before the plants sell out.