Crocus are the real heralds of Spring. As soon as the days lengthen they start growing like mad. It has happened at our nursery that they have blossomed whilst a late February Snow was falling creating a unique effect.
The earliest varieties are called Botanical Crocusses such as our Snow Flowering Mixture of Crocus Chrysanthus. Larger flowering Crocus varieties such as Remembrance, Yellow Mammoth and others belong tho the Crocus Vernus strain. They bloom generally during March depending upon your zone.

Whether in flower beds or in containers, remove any early flower buds to allow the Begonia plant to reach full size as quickly as possible.