How to Grow Sweet Rocket
Hesperis matronalis
Hardy Cool Season Continuous Harvest
Sweet Rocket is a hardy biennial sown in summer, overwintering as a leafy rosette and bursting into fragrant purple, pink, or white flower spikes in late spring. Plant in any reasonable soil in sun or partial shade. Almost no care needed — just deadhead to control spreading or leave seedheads to self-sow freely and naturalise.
In your Leaftide garden - Hardiness
- Hardy
- Season
- Cool Season
- Harvest
- Continuous Harvest
- Spacing
- 45 cm
- Height
- 80 cm
- Start from
- Seed
- Light
- Full sun to part shade
- Water
- Moderate
When to Start
Sow from late spring to midsummer, in trays or where it is to flower. It only grows leaves in its first year and flowers the following spring or summer.
Don't know your frost date? Find it here →
Growth Stages
Sow seeds
Day 0 Germination
~14 days Flowering
~345 days Seed to harvest ~345 days
Approximate days from start
Care Essentials
- Generally no feeding needed. On poor soils, a balanced fertiliser at planting time is sufficient.
- Sweet Rocket is a short-lived biennial or perennial that self-seeds prolifically. Sow in summer, overwinter as a rosette, and enjoy fragrant flowers the following spring. Extremely low maintenance once established.
Growing Conditions
Don't know your frost date? Find it here
- When to Start
- Sow from late spring to midsummer, in trays or where it is to flower. It only grows leaves in its first year and flowers the following spring or summer.
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Spacing & Planting
| Plant spacing | 45 cm |
| Row spacing | 45 cm |
| Mature height | 80 cm |
| Mature spread | 40 cm |
Growing Conditions
| Base growth temperature | 4°C |
Frequently Asked Questions
- How far apart should I plant Sweet Rocket?
- Plant Sweet Rocket 45cm apart with 45cm between rows.
- When does Sweet Rocket flower?
- Sweet Rocket flowers the year after sowing. It spends its first year growing leaves and flowers the following spring or summer.
- Is Sweet Rocket frost hardy?
- Sweet Rocket is classified as Hardy.