Kikuyu grass is an extremely aggressive weed of ornamental plantings and turf throughout California. It thrives within our micro-climate and is very fast growing. It usually turns brown in November and remains dormant until February or March, depending upon the temperature. Its negative impact is vast. Within planting areas it invades ground covers and flower beds; and if not managed, completely chokes them out. It can also invade low-growing shrubs, reducing much-needed light for the plants to remain healthy. Within turf areas, kikuyu grass forms thick mats that crowd-out the desired species.
The best way to manage the infestation which spreads both from seed and stem sections, is to prevent its spread into new areas. It appears to be most commonly spread by mowing, and cultivation. Our best practice at Earthco is to clean equipment to remove any kikuyu grass seed and stem sections before moving out of the infested areas. It can also be known to spread in contaminated soil, sod and planting materials, so we ensure that any incoming new plant material is free of contamination.
Our “best practice” technique to manage infestation is to remove any patches of kikuyu grass as soon as possible. Our goal is to maintain both turf and ornamental planting areas to ensure that they are at their maximum health so that they are as competitive as possible to help slow the invasive weed. Prevention is key as is hand removal or spot-spraying of solitary plants. Hand weeding is the primary method of control in planting areas. Mulching is somewhat effective as it allows less light to penetrate to the soil so new seeds will not germinate as expediently. It is best to use post-emergent herbicides to control kikuyu grass in established garden areas.
Pre-emergent herbicides when applied in March, have proven successful in limiting germination of seed in spring and early summer. To control established plants, multiple applications of a post-emergent herbicide are required, most commonly three to four applications are recommended.