Agastache nepetoides
yellow giant hyssop
A tall perennial, up to around 2m high, with stout, square stems and aromatic, coarsely toothed green leaves up to 15cm long. Dense spikes of tubular, pale greenish-yellow flowers are produced in late summer
Size
Ultimate height
1.5–2.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Yellow Green | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Sheltered Hardiness
H3Botanical details
- Family
- Lamiaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Agastache are herbaceous perennials with simple, aromatic leaves and small 2-lipped tubular flowers in whorls forming dense spikes, in summer and autumn; some are rather tender but can be grown as annual bedding
- Name status
Correct
- Plant range
- E Canada, Central USA
How to grow
Cultivation
Thrives in fertile, moist but well-drained soil in sun or light shade. Dislikes summer drought
Propagation
Propagate by seed or by division in spring. Will self-seed in place in good conditions
Suggested planting locations and garden types
- Architectural
- Cottage and informal garden
- Wildlife gardens
- Flower borders and beds
Pruning
Remove spent flowering spikes as they fade
Pests
Generally pest-free
Diseases
May be susceptible to powdery mildews
Get involved
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