Flower of an hour
Hibiscus trionum · Malvaceae
📷 No machine-readable author provided. Bogdan assumed (based on copyright claims). · CC BY-SA 3.0
The gardener's calendar
Flower of an hour is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Common name
- African Hibiscus
- Family
- Malvaceae
- Type
- Annual or biennial herbaceous plant
- Adult height
- 60 cm
- Flowering
- July to September
- Foliage
- Deciduous
- Hardiness
- Frost-tender (warm climate)
- Origin
- Tropical Africa and Asia
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
Annual-biennial African Hibiscus requires heat and direct sun for 6+ hours: sow in March-April indoors, plant out only in May after the last frost. Water regularly but avoid spraying foliage.
The common mistake
Sowing too early or too late: early sowing produces spindly, weak plants, late sowing misses the summer to flower.
The pro's trick
Remove the first 3-4 flowers to strengthen the plant: you'll get better branching and more abundant flowering from July to October.
Seasonal watch
September-October: nighttime temperatures below 10°C significantly slow flowering.
Care
Light Exposure
Your African Hibiscus demands full sunlight to bloom abundantly. Place it in a bright, warm location sheltered from strong winds. Insufficient light significantly reduces flowering and slows growth.
Watering
Keep the soil moist but well-draining during the growing season. Water regularly without allowing water to stagnate at the bottom of the pot, which causes root rot. Gradually reduce watering in autumn and winter.
Soil
Rich, well-draining, slightly acidic soil works perfectly. Enrich the potting mix with mature compost or organic matter when planting. Ensure optimal drainage to prevent root asphyxia.
Fertilizing
Feed every 15 days with balanced fertilizer or one higher in phosphorus and potassium during flowering. This promotes an abundance of blooms. Stop feeding in autumn when growth slows.
Pruning and Cutting
Pinch young stems in spring to encourage compact branching and a bushy shape. Remove spent flowers regularly to encourage prolonged blooming. At the end of the season, you can cut back the plant if it becomes too leggy.
Diseases and Pests
Watch for spider mites and whiteflies, particularly indoors or in dry climates. Good drainage and good foliage aeration prevent fungal diseases. Regularly inspect the undersides of leaves to detect any infestations early.
Did you know?
Hibiscus trionum is also poetically called the Ephemeral Hibiscus: each of its flowers lasts only one day, opening in the morning and closing in the evening, like a window shutting. Despite this fleeting beauty, the successive and abundant summer flowering makes it a spectacular and generous plant in your garden.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
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- Rose of SharonHibiscus syriacus
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- Silver LimeTilia tomentosa
- Crimean lindenTilia euchlora
- Swamp hibiscusHibiscus moscheutos
Tips generated and checked by Viridia — adapt them to your local climate.