St. Patrick's Day has become a worldwide day to wear green, honoring both the saint and the country he evangelized.
St. Joseph's Day, only two days later on March 19, does not have a widely accepted color.
However, that doesn't mean St. Joseph can't be associated with a specific color.
What might be St. Joseph's color?
Liturgically speaking, priests in the Roman Rite wear white on St. Joseph's feast day. White is the color of holiness, purity, cleanliness, and righteousness. It's the color used for the highest level of liturgical feasts, the solemnity.
In religious iconography, St. Joseph is depicted in a variety of colors.
For example, sometimes St. Joseph wears blue, which is a color most closely associated to the Blessed Virgin Mary. Blue can also represent heaven and points to St. Joseph's heavenly holiness.
Green is another color frequently found on St. Joseph, often on statues and in icons. This color can point to St. Joseph's earthly nature, as well as the "new life" he helped welcome into this world.
Probably one of the most popular colors associated with St. Joseph is brown. The color of dirt and wood, brown is used to symbolize the temporary nature of created things as well as the humility and poverty of individuals.
Brown has also become a primary symbol of St. Joseph due to his carpentry skills and association with manual labor.
If you are looking for a color to wear on St. Joseph's day you have many choices, each with its own symbolism.