Why Spring in New Jersey Makes It Hard to Tell the Difference Spring in New Jersey changes everything at once - trees start blooming, grass grows quickly, and pollen levels climb fast. At the same time, cold viruses don’t just disappear. They’re still making their rounds in schools, workplaces, and public settings. Since both allergies and colds impact your sinuses, throat, and breathing, it’s easy to confuse one for the other. The difference ...