More than once the question rang: why Crimson? It's an unusual color for yoga, how are they related...?
... How are they not?
Technically speaking, colors are a mix of red, green and blue on the RGB pallette.
Looking into each of these colors, here's what they symbolize:
Red: The stimulating red is an attractive color usually associated with passion, liveliness, life, love, high energy, action, intensity, warmth, good luck, and happiness. It's also known to awaken the physical life force, being the color of the burning sun that enables life on earth and the color of the blood that runs in our veins.
Blue: the calming blue is the color of peace and it promotes mental and physical relaxation. Being the color of the skies and the sea, it inspires openness, knowledge and communication.
Green: traditionally the color of nature, green represents, freshness, growth, productivity, health and wealth, it promotes peace, harmony and feelings of safety.
Red, green and blue mix together in various combinations to produce the different colors of the spectrum, and this includes Crimson that's made of largely red, some blue and some green.
All the qualities mentioned above exist in this deep balancing shade of red, much like in Yoga, a profound practice and science that's so much more than peace and zen, it's also about being alive with vigor, love, purpose, and zest for a healthy, well-lived life.