Growing Delphinium

Latin Name Pronunciation: del-fin'ee-um 

Delphiniums require full sun, preferably in a spot protected from high winds. They also need very fertile soil, with a pH close to neutral. If your soil is acid, plan to mix a handful of lime into the bed. And, lastly, all of the tall varieties require staking. Inevitably, a sudden downpour will knock unsupported stems down into the mud, and there's no way to ease that heartbreak. We suggest using two or more loops of twine, arranged in a figure-8, starting near the base and ending just below the flower head.

"Very fertile soil" means soil enriched with plenty of compost or composted manure. Plan to add a balanced, slow-release fertilizer as well.

Yes, Delphiniums require more attention and preparation than some other perennials. But, as our founder wrote, "… no gardener worth his loam would stop growing Delphiuniums just because they are not as rugged as weeds. There is nothing more beautiful or more rewarding …."

Cut the flower stalks of all but D. grandiflorum 'Blue Mirror' to the ground immediately after flowering for a second, smaller show in September. D. grandiflorum 'Blue Mirror' is the best Delphinium for the South but is short-lived there; allow a few plants to go to seed to provide for replacements.

Combine with Peonies, Siberian Iris, Lupines, Shasta Daisies, Roses, and other June bloomers.

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