Controlling Zoysia Grass
Zoysia grass spreads through underground rhizomatous runners. One of the best ways to keep zoysia out of neighboring lawns or garden beds is to establish good borders. You can accomplish this by installing lawn edging that zoysia is unable to get through, such as plastic or aluminum. Place the edging in the ground at least 6 inches (15 cm.) deep with another 2 or 3 inches (5-8 cm.) above the ground to help keep zoysia within its boundaries. Alternatively, those looking to simply eradicate the grass can instead treat the entire lawn area with a non-selective herbicide. While herbicide treatments usually begin in late summer, to achieve the best results, apply the herbicide while the grass is still green and actively growing. Also, keep in mind that non-selective herbicides still have the potential to kill other plants on contact. Therefore, use it with caution when applying near garden plants. Since zoysia is known to regrow, repeated applications will most likely be necessary. Treated areas will eventually turn brown and provided no more zoysia has popped up, it is generally safe to reseed the area within a couple weeks.
Removing Zoysia Grass
For those looking for a non-chemical form of removal, the only option is to remove the grass altogether with a sod cutter. This method works for both large and small areas, however, you may find that smaller areas make the task much easier to accomplish. When removing zoysia grass this way, include some of the topsoil as well to limit the possibility of re-emergence. Once the grass has been removed, wait a couple weeks (removing any new shoots that appear) and then till the existing topsoil, adding more if needed, and reseed. Zoysia grass is a great choice for warmer climates and large lawns where it is free to creep about without invading other nearby areas. However, for those that have already been ‘invaded’ by this quick spreader, containing zoysia grass or removing it altogether may be your only recourse. Note: Chemical control should only be used as a last resort, as organic approaches are more environmentally friendly.