Trust, and loyalty.

Blue is feeling sincere
Slowing patience to all your friends.
Blue is an ocean
Making you feel nostalgic, sometimes blue.
It's the water that spills out of you.
Blue lifts you up,
When you are successful in your studying.
Blue is a cloud and the sky.
Blue is calmness.
You look up and touch it,
When you're low in spirit
And want company.
Peaceful dove, peaceful world
Peaceful quiet, I hear it
And when you feel serenity
Blue runs through your mind.
Blue is a wave,
A single seagull,
Flying in the coastline
Between the sky and ocean.
Blue is a mood,
Blue is a voice,
My mind's notion

Reference

Consider these examples by Mary O’Neill in her collection of poetry from Hailstones  and Halibut Bones. She describes colors using vivid imagery and detail.
Red is sunset
Blazing and bright.
Red is feeling brave
with all your might.
Red is a sunburn
Spot on your nose.
sometimes red
Is a red, red, rose.
Red squiggles out
when you cut your hand.
Red is a brick
and the sound of aband.
Red is hotness
you get inside
when your embarassed
and want to hide.
fire-cracker, fire-engine
fire- flicker red–
and you’re angry
Red runs through your head.
Red is an Indian
a Valentine heart.
the trimmings on
A circus cart.
Red is a lipstick
Red is a shout
Red is a signal
that says “WATCH OUT!”
Red is great big
rubber ball.
Red is the giantest
color of all.
Red is a show-off.
No doubt about it.
but can you imagine
living with out it?