Ferula communis subsp. glauca
glaucous giant fennel
A robust perennial, 3-4m high in flower, forming a mound of aromatic, finely divided leaves that are bright green above and silvery beneath. Stout, branching grey-green stems, often flushed with purple, bear many rounded clusters of small yellow flowers in early to mid summer
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Size
Ultimate height
2.5–4 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Grey Silver | |||
|---|---|---|---|---|
| Summer | Yellow | Green Grey Silver | ||
| Autumn | Green Grey Silver | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H3Botanical details
- Family
- Apiaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Ferula are striking, large tap-rooted herbaceous perennials with big, pinnately divided leaves and compound umbels of small white, yellow or purple flowers; may die after flowering
- Name status
Correct
- Plant range
- Med. to Arabian Pen.
How to grow
Cultivation
Grow in fertile, well-drained soil in full sun; protect with a dry, bracken mulch in winter. May take some years to flower. Plants sometimes die after seeding
Propagation
Propagate by seed, sown in pots in a cold frame as soon as ripe. Prick out seedlings into deep pots to allow tap root to develop
Suggested planting locations and garden types
- Architectural
- Cottage and informal garden
- Gravel garden
- Mediterranean climate plants
- Wildlife gardens
Pruning
To enhance foliage, remove flowering stems as soon as they appear, or after blooming if seed is not required
Pests
Diseases
May be susceptible to downy mildews
Get involved
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