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You know that old saw about plants -- "thrives on neglect"? It must have been created for sea holly. It does best in poor soil with little water and baked conditions. Yet it has striking flowers, an interesting prickly texture, excellent drought- and deer-resistance, and even salt-tolerance. Plants form taproots, so they are difficult to transplant once established, but starting new ones from seed is easy. Remove spent flowers to prevent excess self-seeding.
From 1 to 8 feet
1-3 feet wide
how to grow Sea holly
garden plans for Sea holly
more varieties for Sea holly
Alpine sea holly
Eryngium alpinum has deeply serrated bracts (petals) surrounding a central cone, giving the flower a lacy appearance. It grows 3 feet tall. Zones 5-8
Amethyst sea holly
Eryngium amethystinum is the hardiest species. It bears purple-blue flowers on plants 2-1/2 feet tall. Zones 2-10
Flat sea holly
Eryngium planum has silver-blue flowers on plants 2-3 feet tall. Its leaves are scalloped rather than spiny. Zones 5-10
'Miss Willmott's ghost'
Eryngium giganteum gets its name from its dramatic ghostly gray-green to silvery blue flowers on plants up to 6 feet tall. Also sometimes called giant sea holly. Zones 5-10
Eryngium yuccifolium is a native of the Great Plains. It is a stately plant that reaches 4-5 feet tall and bears silvery white balls on spiny foliage that resembles that of yucca. Extracts of the plant were used by Native Americans as medicine. Zones 4-8
Sapphire Blue sea holly
Eryngium 'Sapphire Blue', also sometimes sold as 'Jos Eijking', is a sterile variety that does not self-sow. Zones 5-9
plant Sea holly with
Yarrow is one of those plants that give a wildflower look to any garden. In fact, it is indeed a native plant and, predictably, it's easy to care for. In some gardens, it will thrive with almost no care, making it a good candidate for naturalistic plantings in open areas and along the edges of wooded or other wild places.Its colorful, flat-top blooms rise above clusters of ferny foliage. The tough plants resist drought, are rarely eaten by deer and rabbits, and spread moderately quickly, making yarrow a good choice for massing in borders or as a groundcover. If deadheaded after its first flush of blooms fade, yarrow will rebloom. If left to dry on the plant, flower clusters of some types provide winter interest. Flowers of yarrow are excellent either in fresh or dried arrangements.
Grow artemisias for the magnificent silver foliage that complements nearly all other perennials and ties together diverse colors within the garden. They're nothing short of stunning next to white or blue flowers.They thrive in hot, dry, sunny conditions such as a south-facing slope. A number spread rapidly to the point of being aggressive, so consider limiting yourself to varieties listed below that are well-behaved.
Daylilies are so easy to grow you'll often find them growing in ditches and fields, escapees from gardens. And yet they look so delicate, producing glorious trumpet-shape blooms in myriad colors. In fact, there are some 50,000 named hybrid cultivars in a range of flower sizes (the minis are very popular), forms, and plant heights. Some are fragrant.The flowers are borne on leafless stems. Although each bloom lasts but a single day, superior cultivars carry numerous buds on each scape so bloom time is long, especially if you deadhead daily. The strappy foliage may be evergreen or deciduous.Shown above: 'Little Grapette' daylily