Tall and stately, delphinium flowers come in purple, white, pink and even yellow blossoms, says Jerry Goodspeed, Utah State University Extension horticulturalist. Recent breeding has even developed hardy delphiniums in red and orange hues. However, the most popular are still the purple, lavender, white and bi-colored varieties. Larkspur are often confused with delphiniums. They reseed themselves most years, so they are often confused with perenials.
Larkspur flowers are a bit smaller, but come in the same wonderful colors as delphiniums.
They are normally sold as mixes, which means you get a large splattering of many colors. They are very showy and bloom throughout most of the summer. Delphiniums bloom on tall spikes, so they are commonly used in borders or as background plants in the landscape, Goodspeed explains. They bloom in early summer and often again in late summer or early fall. The tall spikes of these flowers need some type of support while blooming so they don't fall.