Imagine: You love a few plants that make your summer garden come alive with a perennial that pops. And you also like a flower that turns a run-of-the-mill bouquet into a “WOW!” arrangement. That’s why you planted the ‘Big Blue’ Eryngium and plan to use it in your best friend’s bridal bouquet. After all, any bride can have roses and peonies, but how many can contrast these soft and fragrant flowers with something that’s naturally a metallic blue and prickly? This is a garden plant that can shake things up…

Name: Eryngium x zabelii ‘Big Blue’ aka Big Blue sea holly

Type of Plant: A perennial hardy in Zone 5-9 for full sun and locations with good drainage.

Why I love this: This sea holly has dramatic, bold blue flowers that are so sculptural and unique that after you grow one plant you’ll probably want more. I got a sample of this Eryngium from Blooms of Bressingham as a test plant about five or six years ago and I look forward to the flowers every year.

These plants grow to be 30 to 36 inches tall. They spread slowly, so to make a big show plant three to five of them about two feet apart. I think these are the perfect plant to place in front of a group of Russian Sage because they both appreciate similar growing conditions. The sea holly blooms in early summer and the Perovskia takes over in early August. Between the two of them they’ll provide a stand of lavender-blue flowers all summer long.

A Word to the Wise: Place this plant carefully as it has deep roots and so doesn’t move well after it’s established. Water deeply every week or two in times of drought.

It’s the spiky, thistle-like flowers that are so wonderful in this sea holly.

This plant is perfect with other perennials that like sun and good drainage. Coreopsis, as seen here, is perfect. Daylilies and Russian sage are also good companions.

Here’s the bouquet I made for Molly’s wedding. It has the lovely Big Blue Eryngium flowers included with several other colorful blooms.