These plants are technically perennials, but most gardeners swear by growing them as annuals. Growing them as annuals means you need to bring plant them each year in the spring after the danger of frost has passed.
Once you have successfully dug your bulbs, it’s best to store them properly to avoid killing them. You have already done too much work to want to destroy them.
When storing, cut the plant’s top leaving a bit of stem above the bulb, and remove excess soil. Corms need curing for about 3 weeks in a warm, dry indoor location with good air circulation.