Blue flowers include the blue hydrangea, rozanne geranium, delphinium, brunnera and bluestar. Others include the bellflower, balloon flower and morning glory. These flowers vary in shades of blue and purple.
Blue hydrangeas are sky blue and have large leaves. They grow best in the morning sun, with afternoon shade and in moist soils. Hydrangeas grow up to 7 feet tall.
Rozanne geraniums are violet-blue and thrive from June until the first frost. They grow best with full or partial sun and moist soil. Geraniums grow up to 2 feet tall.
Delphiniums are true blue and prefer regions with cool summers. They grow best with full or partial sun and moist soil. Delphiniums grow up to 6 feet tall.
Brunneras are pale blue and have heart-shaped leaves. They grow best in shade with moist soil. Brunneras grow up to 2 feet tall.
Bluestars are light blue, star-shaped flowers that turn yellow at the end of the season and are resistant to heat and droughts. They also repel deer and rabbits. They grow best in full or partial sun and well-drained soil. Bluestars grow up to 2 feet tall.
Bellflowers are blue, purple, pink or white and are shaped like bells. They grow best in full or partial sun and moist soil. Bellflowers grow up to 3 feet tall.
Balloon flowers are violet-blue, pink or white and are shaped like stars. They grow best in full sun and well-drained soil. Balloon flowers grow up to 2 feet tall.
Morning glories are sky blue and shaped like saucers. They grow best in full sun and well-drained soil. Morning glories grow on vines that can grow over 12 feet tall.