Kikuyu grass (Pennisetum clandestinum) is an invasive perennial grassy weed. It infests lawns, gardens, orchards and abandoned land. Once its established, it can be tough to remove. It grows rapidly and spreads quickly, but is not impossible to get rid of. Kikuyu grass must, however, be treated aggressively for several seasons if it is to be killed for good. After it is gone, you must keep an eye out for new growth and kill it before it spreads.
Dig up individual patches of kikuyu grass. Be sure to dig up all of the roots. Even small pieces can regenerate into new patches. Bag all of the kikuyu blades and roots and throw them away. To kill kikuyu grass this way, you must remain vigilant and dig any new patches that sprout up as soon as you spot them.
Spray kikuyu grass patches with a post-emergent herbicide. The botanists at the University of California Davis recommend treating kikuyu grass with a combination of triclopyr and MSMA herbicides. First spray the kikuyu grass patch with triclopyr according to the manufacturer's instructions. Then, in four to six weeks spray any reemerging kikuyu grass with MSMA. Continue this cycle of triclopyr and MSMA in four- to six-week cycles until the kikuyu grass is killed and does not come back.
Apply a preemergent herbicide labeled for the control of kikuyu grass in spring and again in early summer. Follow the manufacturer's instructions for application rates and amounts.
Spread polypropylene landscape fabric or black plastic tarp over your garden bed to keep kikuyu grass from reemerging.