Galanthus reginae-olgae is a species of snowdrop that is native to many Mediterranean countries. The flowering period extends from September to March, which is the longest spectrum of all snowdrop species. Two subspecies of the Queen Olga's snowdrop have been described: Galanthus reginae-olgae subsp. reginae-olgae is said to be early flowering (i.e. late in the year from autumn to early winter) and G. reginae-olgae subsp. vernalis is said to be late flowering (i.e. in spring). However, because the species covers the entire spectrum and because the many colonies that flower in December and January make it almost impossible to categorise them into one of the two subspecies, the accuracy of this classification can certainly be questioned.
The Queen Olga snowdrop is found in the following countries: Albania, Bosnia and Herzegovina, Greece, Italy, Montenegro and Croatia. Early and late-flowering colonies are known in most countries. Interestingly, autumn-flowering and spring-flowering plants can occur in nature in the exact same location. Because they have two different flowering times, cross-breeding of the plants is impossible. The northernmost colonies are located in the Croatian region of Split-Dalmatia and Tuscany in Italy. The southernmost and best-known colonies are located in the Taygetos Mountains on the Greek peninsula of Peloponnese. The colonies there are considered to be particularly early-flowering and can unfurl their flowers as early as September.