Eryngium bourgatii 'Oxford Blue'
sea holly 'Oxford Blue'
'Oxford Blue' is an erect herbaceous perennial to 40cm, with clumps of deeply divided basal leaves with prominent whitish veins. Cone-like, deep blue flower-heads 2cm in length are surrounded by silvery-blue, spiny bracts
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green White | |||
|---|---|---|---|---|
| Summer | Blue Grey Silver | Green White | ||
| Autumn | Green White | |||
| Winter |
Position
- Full sun
Aspect
West–facing or East–facing or South–facing
Exposure
ExposedDrought resistance
Yes Hardiness
H5Botanical details
- Family
- Apiaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Eryngium can be annuals, biennials or perennials with simple or divided leaves, often spiny edged, and cone-like flower-heads often surrounded by an involucre of conspicuous spiny bracts
- Name status
Accepted
How to grow
Cultivation
Grow in dry, well-drained soil that is poor to moderately fertile. Full sun is essential as is protection from winter wet
Propagation
Propagate by root cuttings in late winter
Suggested planting locations and garden types
- Cottage and informal garden
- Coastal
- Gravel garden
- Wildlife gardens
- Cut flowers
- Flower borders and beds
Pruning
Although you can cut back flower stems after flowering the seedheads are a very attractive feature so are usually left over winter
Pests
May be susceptible to leaf and bud eelworms, and slugs and snails
Diseases
May be susceptible to root rot and powdery mildews
Get involved
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