University of Maryland Extension


Photo & Text by: Christine Pfister McComas

Delphinium grandiflorum

Gardeners can be a romantic, optimistic bunch who fall for plants that, though beautiful, are difficult and buy them anyway. This is true with delphiniums.  Though they come in over 300 species of annuals, biennials and perennials, we are drawn to the brightly colored tall hybrids, stars of the traditional English cottage garden. While delphiniums do well in the Pacific Northwest, they are short-lived in Maryland’s hot humid summers.

A better choice is Delphinium grandiflorum, not as formal looking as other species but happier in our climate. Though short-lived, they don’t need staking or wind protection. They’re primarily available in the famous delphinium blue shades.

Delphiniums as a group prefer full sun and well-drained, basic soil. (Apply lime if your soil test shows acidic.) They are heavy feeders and enjoy a dressing of well-rotted manure or compost as well as a balanced fertilizer. Removing spent flowers encourages more blooms.


Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2020. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.