Rose of Sharon, also known as althea, is a type of hardy hibiscus shrub or tree. It grows 9 to 12 feet in height and has a spread of 6 to 10 feet. It is hardy to USDA zones 5 through 8. It flowers for a long period of time, which is part of its appeal. However, rose of Sharon also sends out suckers that can take over your yard if you're not careful. The best way to kill a Rose of Sharon is to dig it up and remove it.
Cut down all of the foliage from the rose of Sharon with the pruners, loppers and hatchet. Remove all of the foliage to about 1 foot above ground level.
Dig up the rose of Sharon's roots with the shovel. Dig around the shrub in a large circle about 6 feet in diameter to get up all of the roots.
Remove the rose of Sharon from the ground and dispose of it.
Pull up any suckers from the rose of Sharon as they appear. They will eventually stop growing.