The name Hydrangea comes from the Greek word meaning vessel. It signifies devotion, friendship, and understanding. Hydrangea flowers are available locally from within the United States in the summer and fall in shades of blue, pink, white, and purple. Certain colors and varieties are available from South America year round. Dutch hydrangeas are grown in an array of rich colors and unusual shades. They are pricey and available only at select times of the year.