Mountain sandwort
Arenaria montana · Caryophyllaceae
📷 Mtiffany71 · CC BY-SA 4.0
The gardener's calendar
Ideal time to plant mountain sandwort: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Evergreen, fine and linear
- Flowering
- May to July, white flowers
- Adult size
- 15 cm tall, spreading habit
- Growth
- Slow to moderate
- Hardiness
- Very hardy, down to -15°C
- Origin
- Mountain ranges of central and southern Europe
- Soil type
- Well-drained, gravelly, poor to moderately fertile
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
Arenaria montana hates waterlogging: very coarse drainage is essential. Plant it in a raised bed or rock garden, in very poor and stony soil.
The common mistake
Amending the soil or watering regularly weakens this alpine plant.
The pro's trick
Mulch with white gravel or small stones right up to the base: this maintains drainage, reduces moisture at the collar, and prevents damping off during wet winters.
Seasonal watch
Damp autumn (September-October) is its worst enemy.
Care
Watering
Water moderately during the growing season, then reduce during dry periods. Once established, this plant tolerates drought very well thanks to its deep root system. In winter, drastically reduce watering to prevent root rot.
Exposure
Plant mountain sandwort in full sun to encourage abundant flowering and compact growth. It thrives in very sunny, windy locations, ideal for rock gardens and alpine settings.
Soil and drainage
Choose very well-drained soil, slightly acidic to neutral, with added gravel or pumice. This plant hates waterlogging and overly rich soil, which promote damping off and rot.
Pruning and deadheading
Remove spent flowers after blooming to extend ornamental value and encourage a second flush of seed. No structural pruning is needed; simply cut back any dead or damaged growth in late winter.
Fertilizing
Don't apply rich fertilizer: a very light spring feeding is more than enough. Mountain sandwort prefers poor soil and moderate fertility to maintain its natural habit and vigor.
Pest and disease prevention
In dry, well-drained conditions, this plant is very resistant. Ensure good drainage to prevent root rot or damping off. Slugs may nibble foliage in damp conditions.
Did you know?
Mountain sandwort is a pioneer plant of scree slopes and rocky hillsides: it colonizes the harshest terrain thanks to its deep roots and extreme adaptation to drought. Over the centuries, it has inspired alpine botanists and remains essential in Mediterranean rock garden design.
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.
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Tips generated and checked by Viridia — adapt them to your local climate.