Eryngium Big Blue (Sea Holly)
This perennial is semi-evergreen so it can lose some of its leaves in winter. In colder regions or more exposed gardens, it may lose them all, but then fresh new growth appears again in spring.
Position: full sun
Soil: dry, well-drained, poor to moderately fertile soil
Rate of growth: average
Flowering period: July to August
Hardiness: fully hardy
The attractive, dark green, marbled foliage, which appears before the flowers, is shown off to best effect planted in gravel. Or try it in bold clumps among grasses. Eryngiums are also perfect for use in dried flower arrangements.
Garden care: Lift and divide large colonies in spring. Avoid the temptation to cut back the flower-heads in autumn as they provide interest in the winter garden.