The eucalyptus silver dollar plant (Eucalyptus polyanthemos), also known as the silver dollar gum, produces highly fragrant, evergreen foliage. Shrubby in appearance, the eucalyptus silver dollar plant blooms from spring until winter, producing pink or white fluffy flowers that contain honey. Eucalyptus silver dollar plants prefer to grow in full sun and well-drained soil within USDA hardiness zones 8 through 10. With proper care, most gums will grow to 50 feet tall with a 40-foot spread at maturity.
Water the eucalyptus silver dollar plant weekly. Use a drip ring to supply the silver dollar with 5 to 20 gallons of water per week for the first two years. The plant will need 15 to 20 gallons of water twice a month during year three and as needed thereafter.
Prune the eucalyptus silver dollar in the early spring. Use a pruning tool to remove dead, damaged and inward growing branches. If you prefer the shrubby look, only minor pruning is necessary. But for a tidy, tree-like appearance, all suckers (secondary branches) must be removed that do not extend directly from the center trunk. This tidying up should be done yearly.
Feed the silver dollar plant a slow-release fertilizer. Follow the packaging instructions for allocation amounts and application recommendations. Eucalyptus silver dollars appreciate a dose of fertilizer in the early spring before new growth begins.
Mulch around the eucalyptus silver dollar with a 3- to 4-inch layer of bark chips. Mulching improves drainage and reduces weed growth under the canopy of the tree. Leave a 6-inch distance between the wood of the silver dollar and the mulch to prevent pest infestations.
Contact a professional arborist if pests infest the eucalyptus silver dollar plant. The silver dollar is susceptible to infestations by the eucalyptus beetle. A professional arborist can diagnose the infestation and draw up a remediation plan.