With Orange residents restricted to one hour of watering a week keeping gardens alive is testing most gardeners around town.

FOBG president Susan Sanders said most varieties on sale were hardy.

"Most of the salvias are pretty resistant, the daisies too, succulents withstand drought very well. And agapanthas are drought-tolerant, as well as the centaurea," she said.

Mrs Sanders said buyers could plant them now.

"People can either plant most of them now in the cool of the day or leave them in a shady spot and keep them watered until we get better weather," she said.

She said mulching and deep watering of plants was best for gardens.

Mrs Sanders said the Botanic Gardens' plants had been grown from seedlings and cuttings and benefited from being so far not limited to Level 5 restrictions which cover residential gardens.

"According to the head of the Parks and Gardens we're not using enough water to affect things at the moment," she said.

The plant sale runs from 8am-11am. Prices range from $1 for tube stock to $2-$3 for most plants and $5 for some large, round, pots.

Receive our free newsletters delivered to your inbox, as well as breaking news alerts. Sign up below ...