Culture
Winter hardy to USDA Zones 8-10 (Zone 7 with protection) where it is best grown in organically rich, fertile, consistently moist but not wet, well-drained soils in full sun to part shade. Fertilize plants regularly during the growing season. Best growth occurs in full sun, but plants tolerate and sometimes appreciate part shade or light filtered sun in the heat of the day. Site in locations protected from strong winds. Bananas are typically grown from suckers (pups) that are planted outdoors or in containers.
Bananas are monocarpic (each trunk-like pseudostem sets fruit only one time and then dies), with the plant surviving from year to year by the suckers (known as pups) which develop at the base. It is best to allow 2-3 suckers to develop around the pseudostem each year. When the main pseudostem produces fruit and dies, the largest of the suckers develops into a replacement pseudostem.
Banana culture is relatively simple in frost free winter climates. In colder winter climates, the culture becomes more complicated, particularly if harvesting fruit is a goal as opposed to growing the plants for ornamental purposes only. Banana plant growth stops when temperatures consistently dip below 50 degrees F. Fall frost will kill the leaves. Trim leaves back to the pseudostem after the first fall frost. It is important to keep the pseudostem as tall and protected as possible over winter to promote good fruit for the following year. It is less important to retain tall pseudostems in winter if fruiting is not a primary concern. If the pseudostem is cut back significantly or dies to the ground, the plant may survive winter but no fruit will appear the following year.
Regardless of climate, bananas can always be grown in containers as tender perennials which must be overwintered indoors where winter temperatures dip below freezing.
'Siam Ruby' is hardy in Zones 9-11. Plant in full sun for the deepest red color.
Noteworthy Characteristics
Musa is a genus of 40 species of evergreen, suckering, herbaceous perennial plants from Northeast India and Bangladesh and from Southeast Asia to Japan and North Australia. Species, hybrids and cultivars are grown for their edible fruits as well as their showy, tropical foliage.
Genus name honors Antonia Musa, Roman physician of the 1st century B.C.
'Siam Ruby' is a banana selection that features colorful foliage and compact habit. Mature plants will reach up to 8' tall and spread to fill a 6' area. The foliage and stems are dark maroon red, with the leaves also sporting spots and streaks of contrasting chartreuse green. This selection rarely flowers, and fruits are not palatable. But if flowers are formed they are cream colored and tubular in shape, held in clusters between cream and purple bracts.
Problems
Grasshoppers, borers and root nematodes may attack outdoor plants. Susceptible to anthracnose, wilt and mosiac virus. Watch for aphids, spider mites, mealybugs and scale on houseplants.
Uses
Can be effective as a garden centerpiece or for tropical flair near patios or bodies of water. Suitable for use in large containers. This cultivar does not flower readily, and the fruits are heavily seeded and unpalatable.