Experiments with Cyperus rotundus L. III. Seasonal variations in growth

Summary Nutgrass tubers were planted in pots on thirteen occasions at 4‐weekly intervals, and growth and development followed by sampling at 5‐day intervals from 10 to 45 days after planting. Growth rates, final shoot numbers, dry weights and rhizome lengths, and new tuber production were highest in plantings made 1 and 29 March and 26 April. Correlation coefficients suggested that mean daylength during growth was a major factor influencing growth and development, but mean temperature appeared to be important in determining new tuber size and the proportion of dry‐matter as new tubers. Shoot number appears to be a reliable guide to rhizome and tuber production.