sentences:  Usually a seeding rate of 13 – 20 kg/hectare (12 – 25 lb/acre) is recommended, with differences based upon region, soil type, and seeding method.A nurse crop is sometimes used, particularly for spring plantings, to reduce weed problems and soil erosion, but can lead to competition for light, water, and nutrients.In most climates, alfalfa is cut three to four times a year, but it can be harvested up to 12 times per year in Arizona and southern California.