How to grow Spirea in the UK
Spiraea japonica
Spirea (Spiraea japonica) is a flower that grows well in UK gardens. Indestructible. Hard prune annually keeps shape compact and bloom-heavy. This guide covers when and how to sow Spirea, the soil and position it likes, watering and feeding, companion planting, and when to harvest.
When to sow & grow Spirea
Sowing and harvest window through the year (UK):
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct Plant | Nov | Dec |
Soil, position & care
- Soil
- Most well-drained soils with added organic matter
- Soil pH
- 6.0–7.5
- Position
- Sun or part shade depending on species
- Sowing depth
- Plant so the rootball top sits level with the soil
- Spacing
- Allow for mature spread
- Sowing
- Plant from containers spring or autumn; water in well
- Growing
- Water through the first two summers; mulch annually
- Harvest & upkeep
- Prune to shape after flowering; remove dead/crossing wood
- Watch for
- Generally tough; watch aphids and powdery mildew
Companion planting for Spirea
No specific companion notes for this plant.
Add Spirea to your free 12-month plan and get watering & sowing reminders — no sign-up needed.
Spirea FAQs
How much sun does Spirea need?
Spirea prefers full sun (6+ hrs direct).
When should I plant Spirea in the UK?
In the UK, plant Spirea in October. Planting in this window gives the roots time to establish before the plant is asked to grow away.
Is Spirea easy to grow?
Easy — good for beginners. Indestructible. Hard prune annually keeps shape compact and bloom-heavy.