Two experiments investigated (1) the effect of stage of maturity at harvest in the first year on yield and persistency of red clover and lucerne when grown as monocultures and bi-crops, and (2) the effect of ensiling differing ratios of red clover and lucerne on forage quality and degree of proteolysis. Red clover (cv. Milvus) and lucerne (cv. Vertus) were established in triplicate plots at five sowing ratios:1·00 red clover, 0·75 red clover:0·25 lucerne, 0·50 red clover:0·50 lucerne, 0·25 red clover:0·75 lucerne and 1·00 lucerne. In year 1, plots were harvested in three strips, at different stages of plant maturity, either 11 (early), 13 (mid) or 15 (late) weeks after sowing. In years 2 and 3, the whole plot was harvested at each of four harvests taken during the growing season. The DM yield of lucerne in years 2 and 3 was higher than that of red clover, leading to increased yields from bi-crops with increasing proportions of lucerne. Strips harvested at the mid-stage of maturity in the first year on the 0·25 red clover:0·75 lucerne plots produced the highest DM yields overall. Ensiling red clover and lucerne bi-crops was found to combine the improved wilting properties of lucerne and the reduced proteolysis of ensiled red clover.