NOW is an excellent time to plant up a dry and shady bed. The winter and spring rains have made the soil easier to dig, and the deeper down you can go - incorporating plenty of water-retaining organic matter - the better. If you reach subsoil, which is generally a lighter, more dead-looking type of material, break it up with a fork or spade and work some manure or compost into it.
After planting up the bed, it is essential to keep it well watered - and mulched, to conserve moisture - for at least a year. This allows the plants to make strong, far-reaching roots that are able to draw on water deep in the ground during times of stress.