Scleranthus annuus
Scleranthus annuus · Caryophyllaceae
The gardener's calendar
Ideal time to plant scleranthus annuus: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Family
- Caryophyllaceae
- Type
- Annual herbaceous plant
- Adult size
- 10 to 30 cm tall
- Foliage
- Deciduous (disappears in winter)
- Flowering
- June to September
- Hardiness
- Hardy, tolerates cold
- Origin
- Temperate Europe
- Exposure
- Full sun to partial shade
Care
Exposure
Position your annual knawel in full sun or partial shade for balanced growth. A bright location promotes compactness and better flowering. Avoid dense shade areas that would slow down development.
Soil and planting
This plant appreciates well-drained soils, poor to moderately rich. It tolerates dry and rocky terrain, even rock gardens. Excessive winter moisture can be harmful; improve drainage if necessary.
Watering
Water moderately during the growing period, allowing the soil to dry out between waterings. In summer, occasional watering is generally sufficient. Reduce watering considerably in autumn and winter.
Fertilizer
Fertilizer is not necessary on poor soils, where this plant thrives naturally. On rich soil, a light spring application is sufficient. Avoid excess nitrogen, which would promote foliage at the expense of flowering.
Pruning and maintenance
No specific pruning is required; the plant naturally maintains a compact form. Remove dead or degenerated parts in spring. As this is an annual, pull it up after autumn decline.
Diseases and pests
Annual knawel is little susceptible to diseases and pests. Excessive moisture can promote rot. Check for spider mites in very dry and hot climates.
Did you know?
Annual knawel bears an evocative name: 'sclero' means 'hard' in Greek, referring to its very tough and difficult-to-crush fruit. This small pioneer herbaceous plant naturally colonizes disturbed terrain and slopes, playing the role of an 'ecosystem cleaner'.
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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Tips generated and checked by Viridia — adapt them to your local climate.