Eryngium agavifolium

agave-leaf sea holly

  • © Richie Steffen / Great Plant Picks

  • © Richie Steffen / Great Plant Picks

  • © Richie Steffen / Great Plant Picks

Outstanding Qualities

The agave-leaf sea holly is distinctive foliage perennial for the Northwest. Since agaves do not like our cold and wet winters, with a little imagination this can serve as a good substitute. The architectural quality of the flat, semi-evergreen rosette adds interest to the sun garden. Each glossy dark-green leaf is about 16 to 24 inches long, sword-shaped with a sharply-toothed edge. In late summer it puts up a 4-to-5 foot flower stem bearing a spiny group of 2-inch, greenish-white, thimble-shaped blooms. As the season progresses the flowers mature to a dark chocolate-brown and last until mid-winter. This plant looks good with other sun and drought loving perennials such as Salvia greggii, Acanthus mollis, shrub roses, verbascum, blue oat grass and hebes. Eryngium agavifolium is quite attractive to bees and butterflies and is also deer resistant.

Quick Facts

Plant Type: perennial

Foliage Type: semi-evergreen

Plant Height (10-year): 2 ft. 0 in. (0.61 meters)

Plant Width/Spread (10-year): 4 ft. 0 in. (1.22 meters)

Hardiness: USDA Zones 6 to 9

Flower Color: white

Sun/Light Exposure: full sun to light shade

Water Requirements: drought tolerant when established

Wildlife Associations: bees, butterflies

Resistant to: deer

Culture Notes

This sea holly grows best in well-drained and sandy soil in full sun to light shade. Once established it is very drought tolerant. This tough perennial is relatively short lived, but will reseed into the garden. Spare seedlings are easily removed or relocated as young plants. Remove the flower stems when they are no long attractive and older yellow and brown foliage can be pulled free from the evergreen rosette in late fall and winter.