How to Grow Osteospermum
Osteospermum ecklonis
When to Start
Sow indoors 9 weeks before last frost, or direct sow outdoors after frost risk has passed and soil reaches 12°C.
Don't know your frost date? Find it here →
Growth Stages
Approximate days from start
Care Essentials
- Balanced liquid feed fortnightly during the growing season. Switch to high-potash feed once flowering begins to sustain continuous blooms.
- Osteospermum are tender perennials from South Africa, grown as half-hardy annuals in the UK. Their daisy-like flowers close at night and in overcast weather, which is perfectly normal. They flower prolifically from late spring to the first frosts in a sunny, sheltered spot. Take cuttings in late summer to overwinter under cover.
Companion Planting
—
Growing Conditions
Get a personalized schedule for Osteospermum based on your exact frost dates
Start planning freeEnter your last frost date to see your dates
- Sow indoors
- —
- Transplant out
- —
- First harvest
- —
Want your full season plan with reminders? Try Leaftide free
Spacing & Planting
| Plant spacing | 30 cm |
| Row spacing | 40 cm |
| Sow depth | 0.3 cm |
| Mature height | 45 cm |
| Mature spread | 45 cm |
Space 25-30cm apart for bedding displays. Osteospermum spread to form bushy mounds 30-45cm wide. They work well in containers, raised beds, and sunny borders.
Care Guide
- Feeding
- Balanced liquid feed fortnightly during the growing season. Switch to high-potash feed once flowering begins to sustain continuous blooms.
- Watch for
-
- Aphids
- Whitefly
- Downy mildew
- Crown rot
Pests & Diseases
Pest Aphids
Identification: Clusters of small green insects on shoot tips and flower buds, causing distorted growth and sticky honeydew.
- Squash by hand or blast off with a water jet
- Spray with fatty acid-based insecticide
- Encourage ladybirds, lacewings and hoverflies
- Spray with a contact insecticide containing deltamethrin
Pest Whitefly
Identification: Tiny white-winged insects on the undersides of leaves. Clouds of white flies when plant is disturbed. Sticky honeydew and sooty mould on leaves.
- Hang yellow sticky traps near plants
- Introduce Encarsia formosa parasitic wasps under cover
- Spray with fatty acid-based insecticide
- Spray with a systemic insecticide containing acetamiprid
Disease Downy Mildew
Symptoms: Yellow patches on upper leaf surfaces with grey-purple fuzzy growth on the undersides. Leaves may curl and drop.
Treatment: Remove and destroy affected leaves. Improve air circulation. Avoid overhead watering.
Prevention: Space plants well. Water at the base. Ensure good ventilation. Avoid overcrowding.
Disease Crown Rot
Symptoms: Plant wilts and collapses at the base. Stems become soft and brown at soil level. Often fatal.
Treatment: Remove and destroy affected plants. Improve drainage. Do not replant in the same spot.
Prevention: Ensure excellent drainage. Avoid overwatering. Do not plant too deeply. Keep mulch away from stems.
Disease Grey Mould (Botrytis) Botrytis cinerea
Symptoms: Fuzzy grey mould on flowers, stems and leaves, especially in humid conditions. Flowers may rot.
Treatment: Remove and destroy affected parts promptly. Improve ventilation.
Prevention: Deadhead regularly. Space plants well. Avoid overhead watering.
Growing Conditions
| Min. soil temperature | 12°C |
| Germination temperature | 18–22°C |
| Base growth temperature | 8°C |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant Osteospermum?
- Plant Osteospermum 30cm apart with 40cm between rows.
- When does Osteospermum flower?
- Osteospermum typically flowers approximately 60 days after transplanting.
- Is Osteospermum frost hardy?
- Osteospermum is classified as Half Hardy.
Plan Osteospermum in your garden — get personalized frost-date scheduling
Start planning free