Delphiniums are one of my favorite summer flowers so I grow plenty and use them generously in bouquets. I mostly grow Delphinium elatum, which produces dense 1-2 foot spikes of flowers in deep blue, pale blue, purple, pink, white and lavender. Each floret in a Delphinium elatum spike has a white or dark brown contrasting center that is picturesquely called a “bee”. I also grow a few Delphinium belladonna, which produces less dense spikes in electric and pale, icy blues.
Purple and lavender delphiniums with salmon lily, white astilbe and daisies
There are numerous delphinium seed strains available but the most common Delphinium elatum series are ‘Pacific Giants’, ‘Magic Fountains’ and ‘Clear Springs’. ‘Pacific Giants’ grow 6 feet tall or more and are striking in a perennial border but they must be staked. For cut flowers I prefer ‘Magic Fountains’ and especially ‘Clear Springs’. Catalogs claim ‘Clear Springs’ grows 30 inches tall but mine usually reach 4 or even 5 feet and still do not require staking. I have less experience growing ‘Magic Fountains’ which seems to grow a bit shorter for me, around 3 feet. There are fewer Delphinium belladonna seed strains, the most common being the pale blue 'Clivenden Beauty', the dark blue 'Bellamosum', and the white 'Casa Blanca'.
I love delphiniums for cut flowers because of their shape, color and long bloom season. The tall spikes contrast beautifully with large round flowers like peonies, lilies, zinnias and dahlias. I also like them combined with lisianthus. I like to combine blue delphiniums with yellow, white or pink and the purple ones look great with orange. Most pink delphiniums are a kind of dusty rose color which looks nice with green nicotinia or deep purple lisianthus. Delphiniums sown in January or February will bloom in July of the same year, and the following year will flower at their normal time in early June and will rebloom in August and September. This means if you start some each year you can have delphiniums in bloom for two months or more of the year.