Purple Annual Flowers

Cape Daisies

• Cape daisies (Osteospermum x hybrida) are hardy annual flower that resemble true daisies. With pale to vibrant blooms in a variety of color options, the cultivar Springtime Mix includes purple flowers and shiny green foliage, according to the University of Illinois Extension HortAnswers. Growing to a height of 12 to 18 inches tall, cape daisies thrive in full sun exposure and prefer moist, well-drained soil. Bloom time is from May through October.

Heliotropes

• Heliotropes (Heliotropium arborescens) are aromatic annual plants that display purple blossoms. The cultivar 'Fragrant Delight' exhibits deep purple petals on fragrant blooms that lighten as they mature, according to the Michigan State University Extension. Blooming from July to September, heliotropes reach a height of 24 inches. These annual flowers thrive in full sunlight and most soil types, but perform best in soil rich in nutrients kept moist during periods of warm temperatures.

Browallias

• Browallias (Browallia species), also referred to as amethyst flowers, are shade-loving annuals that are suitable for both indoor and outdoor use. Reaching a height of 18 inches, browallias produce purple to blue-purple or white flared flowers that bloom during the summer season, according to the University of Missouri Extension. Browallias thrive in partial shade with a preference for shaded afternoons and dry soil.