Description Delphinium flowers beautify the summer garden with showy, spiky blooms on a tall, sometimes towering stem. Delphiniums come in a range of shades. Many gardeners wonder how to grow delphinium and some avoid planting them after hearing that the plant is difficult to grow. What are the secrets to the correct care of delphinium? Read more for tips about delphinium planting and how to get the best performance from growing delphinium plants. Delphinium Information One commonly thinks of delphinium plants (Delphinium) as having true blue flowers, which is the most common color. But numerous hybrids are available in shades of pink, lavender, red, white and yellow. Blooms may be single or double. Delphinium planting is normally at the back of the bed, where flower spikes can reach 2 to 6 feet tall. Delphinium flowers are often planted in masses or groups. Shorter varieties are useful in other areas of the garden.