They produce from roots planted in the spring and should be handled similarly to tuberous begonias. Cannas range from ivory and yellow through rose and salmon to crimson and scarlet. The foliage is either green or bronze. Plant the roots 6 inches deep and 18 inches apart in late spring. After frost kills the foliage, dig and store the roots over winter much the same as dahlias.
Dahlias come in nearly every color except blue.
The typical dahlia reaches a height of 6 feet and requires support, usually provided by a stake driven 12 inches into the ground and 6 inches behind the root at the time of planting. Dahlias do not tolerate frost and should not be planted if there is a chance that the shoots will freeze. The size of individual flowers may be increased by removing the buds from the lateral branches. However, this practice decreases the overall showiness of the planting. After the stalks are killed by frost, remove them, leaving a 6-inch stub.