| Scientific Name: | Eryngium planum |
| Common Name: | blue sea holly, flat sea holly |
| Family Name: | Apiaceae |
| Origin: | Europe |
| Hardiness Zone: | Zone 5: (-29 to -23 °C) |
| Plant Type: | Broadleaf evergreen |
| Mature Size: | 0.7 - 1.3m x 0.3 - 0.6m (height x width) |
| Habit: | Upright |
| Form: | Oval - vertical |
| Texture: | Coarse |
| Landscape Uses: | Attract beneficial insects, Attract butterflies, Container planting, Cut flower or foliage, Dried flower or fruit, Fall interest, Perennial border, Rock garden, Small garden/space, Summer interest |
| Exposure: | Full sun |
| Soil or Media: | Well-drained |
| Leaves: | Simple, Alternate, Basal, Leathery, Glabrous, Elliptic, Oblong, Ovate, Dentate, Palmately lobed, Spinose |
| Flowers: | Umbel, Blue, Jun-Jul-Aug |
| Fruit: | Schizocarp, Brown, Aug-Sep-Oct |
| Key ID Features: | |
| Stems grey-white to purple, 0.7-1m tall, clumping; basal leaves ovate-elliptic, most 5-8cm long x 2-5cm wide, 7-9 palmate veins, prominent on both surfaces, base cordate, margin dentate with small spines, petioles 6-13cm long; stem leaves sessile, ovate-oblong, most 7-10cm long x 3-6cm wide, with 3-5 lanceolate lobes, leathery, margin serrate with larger spines; flowers tiny and clushered in head-like umbels, 8-15mm long x 7-13mm wide (1 to 4 may arise from common node), bracts 1.5-3cm long, blue/blue-green, Jul-Aug. | |