Eryngium planum
Blue eryngo, Flat sea holly
- Height × spread
- 0.8m × 0.4m
- Position
- Full sun
- Hardiness
- Very cold to -20C (RHS H6)
- Flowers
- Summer, Autumn
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
The plant arises from a rosette of oblong leaves, each held on a long stout stalk. From this base arise the flowering stalks that culminate in a ferment of blue knobs each surrounded by a spiky blue collar. The colours fade to brown and silver but the effect retains interest. This is summer flowering and makes a striking feature, beloved by bees.
- Flower colour
- Blue
- Foliage colour
- Grey
- Autumn foliage
- Grey-white
- Variegated
- No
- Scent
- No
- Shape
- Bell
- Height
- 0.8m
- Spread
- 0.4m
- Season of interest
- Summer, Winter
- Flowers in
- Summer, Autumn
- Evergreen
- Deciduous
- Garden style
- Seaside garden, Prairie garden, Gravel garden
- Sun or shade
- Likes full sun
- Soil type
- Chalk, Loam (normal)
- Soil pH
- All types
- Drainage
- Well drained soil, Dry soil, Drought resistant
- Hardiness
- Very cold to -20C (RHS H6)
- Borders & containers
- Borders
- Use for
- Deer resistant, Rabbit resistant, Bee attraction, Butterfly attraction
- Hazards
- No
Spring
Spring-Autumn · Outdoors
Water in dry periods
Established plants in the ground can cope with 7-10 days of dryness, and shrubs often manage 2 to 3 weeks. Water one section of the garden thoroughly each day rather than a little everywhere. Check plants in pots more often, especially in hot weather.
Spring - early-mid · Planting
Divide when too large
The plant can be divided if it becomes too large or another plant is required. This may involve physically dividing the clump in two, removing offsets or small bulbs or dividing rhizomes. The new plants can be grown in pots or planted in the ground.
Summer
Summer - early · Outdoors
Feed a general fertiliser
Where plants have moderate needs for nutrients, they can simply be given a general feed, fairly early in the growth season so that the growth has plenty of time to harden off before the cold weather.
Give plants a general boost with the application of a general purpose fertiliser which is spread around the root area of the plant, with amounts as directed on the feed label.
Found in
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