Animal feed remains the principal constraint to livestock development in the Sahel. This study aims to examine the influence of irrigation frequency and cutting interval on the productivity of two alfalfa varieties (Dynamo and Sunter) cultivated under irrigation in the Sahelian zone of Niger. The experimental set-up consisted of an initial split-plot trial in which the main factor was the variety and the secondary factor the irrigation frequency. Following this first experiment, the same design was reproduced, this time considering the cutting interval as the secondary factor. The results revealed emergence rates of 10% for the Dynamo variety and 8% for the Sunter variety. The irrigation regime involving two consecutive days of watering followed by two days of rest produced the highest number of shoots (12.5 ± 3.1), a main stem height of 36.3 ± 2.0 cm, and an average forage yield of 130 kg DM/ha for Dynamo. For Sunter, daily irrigation resulted in 10.4 ± 5.6 shoots, a main stem height of 31.3 ± 12.1 cm, and a high yield of 85.5 kg DM/ha. Regarding cutting frequency, the highest forage production for Dynamo was obtained with an 18-day cutting interval (133.9 kg DM/ha), compared with the other treatments. For Sunter, the 21-day interval yielded the highest production (135 kg DM/ha). Consequently, the average dry-matter forage production over a two-week period under the irrigation-frequency treatments was 27.8 kg DM/ha for Dynamo and 19.9 kg DM/ha for Sunter. Under the cutting-frequency treatments, average forage production over a 24-day period was 28.8 kg DM/ha for Dynamo and 19.6 kg DM/ha for Sunter. Given the conditions under which this experiment was carried out, alfalfa cultivation appears highly promising. Substantially higher yields can be expected when it is grown under more favourable conditions.