Is 'Spring' Capitalized? Clear Examples and Quick Visual Reference
The difference between capitalizing March and lowercasing spring comes down to the fundamental boundary separating proper nouns from common nouns. English capitalizes proper nouns to mark a specific, uniquely named entity. Days of the week and months of the year derive directly from proper names of Roman gods, Germanic deities, and celestial bodies. January honors Janus; Thursday honors Thor; July honors Julius Caesar.
Seasons evolved differently. Words like "spring," "summer," "fall," and "winter" originated as generic descriptions of agricultural conditions and weather cycles. The term "spring" entered Middle English as a shorthand description for the season when plants literally "spring from the earth." Because these seasonal terms describe generalized recurring weather conditions rather than a single distinct entity, lexicographers categorize them as common nouns.
This classification applies to derivatives as well. You lowercase "springtime," "springlike," and "vernal." Unless a seasonal term carries specific naming rights, standard English syntax leaves it in the lower register.