Production potential of Italian and Westerwolds ryegrass established at different planting dates

Abstract

Fodder flow planning is essential for dairy-pasture systems because its implementation allows fodder to be available throughout the year. Italian and Westerwolds ryegrass varieties (Lolium multiflorum var. italicum and westerwoldicum, respectively) are temperate annuals often planted in the southern Cape region of South Africa. The monthly production potential of these grasses could be manipulated by planting date. The aim of this study was to determine the pasture production potential of Italian and Westerwolds ryegrass planted at different planting dates. Four cultivars of each variety were evaluated by sowing each cultivar in a factorial arrangement in a randomised complete block design every 28 days for two years. Planting date influenced the production potential of both varieties. If the requirement of a fodder flow programme is to provide fodder from May until November, which includes the critical winter months, Italian ryegrass is a better option than Westerwolds ryegrass and should be planted during February or March. If the aim is to have high production in spring and early summer, Italian ryegrass should be planted during May or June. Regardless of the variety, annual ryegrass should not be planted later than June.