Pinch off the old flowers on each stem as they wilt and die off. Grasp the withered bloom behind flower and break it off flush with the stalk.
Cut off the entire stem at the base once all the flower buds have finished flowering. Dispose of the old flower stalk after removal.
Prune back the foliage to within 2 inches of the soil once it yellows and dies back naturally in fall, usually after the first frost. Dig up the corms after foliage removal.
Spread the corms out in a warm, well-ventilated room to dry for three weeks. Pull the remaining foliage off the corms once they are completely dried. Store in paper bags in a dry 40- to 45-degree-Fahrenheit location until spring.