Cannas are tender herbaceous perennials. They prefer a rich, moist soil in a warm, sheltered area of the garden, but can be grow in containers that are sunk into the border soil, so they can be brought in over the winter. Plant out at the end of June and feed with a nitrogen rich feed, changing to potassium rich feed once the flower spikes start to show.
They will continue to flower until first frosts. To protect in the ground over winter, after the first frost, cut the leaves to about 15cm (6in) and cover with straw, tying loosely with twine to stop the straw being blown away. If growing in a pot, after they have been hit by the frost, knock them out of their container, remove all but 15cm (6in) of top growth, remove the soil from the roots/rhizome and keep in trays of dry sand in a garage or dark shed.
Cultivars and varieties:
Seeds to plant now:
Indoor or in a heated greenhouse
Aubretia, Rock cress, Aubrieta, Aubrietia
Outside under cover