Caucasian Rock Cress | Perennial | Groundcover | Rock Gardens
For optimal germination rates, initiate seed propagation indoors under controlled conditions—unless the species exhibits a high sensitivity to root disturbance. This approach allows precise regulation of temperature, humidity, and light, improving germination consistency and seedling viability. Do not skip any recommended seed treatments, as they are essential for uniform and successful germination.
Keep soil evenly moist during germination. DO NOT LET IT DRY OUT—once seeds begin absorbing water (imbibition), drying can kill the seed embryo, and even brief dryness after sprouting can kill seedlings.
Seed Treatment
• Soak seeds in lukewarm water for 6–12 hours to soften the seed coat.
• Optional: Treat with a mild GA3 solution (50–150 ppm) only if you are experienced — improper use can damage seeds.
• Cold stratification required:
Place seeds in a damp paper towel, seal in a plastic bag, and refrigerate (not freeze) for 3–4 weeks.
Check weekly: If seedlings sprout in the fridge, remove and plant immediately.
After stratification, allow seeds to warm to room temperature before sowing.
When to Sow
• Indoors: Late winter to early spring, 6–8 weeks before last frost
• Outdoors: Early spring or fall (in mild climates)
Germination Temperature
• Ideal: 60–68°F (15–20°C)
• Keep soil consistently moist (not wet) during germination
Germination Time: up to 60 days AFTER stratification
Light Requirements
• Use grow lights to maintain 12–16 hours of light per day.
Sowing Instructions
• Use fine seed-starting mix or 50% sand + 50% compost
• Press seeds lightly onto the surface; do not cover
• Mist gently to avoid dislodging seeds
Humidity: Use a humidity dome or clear cover to maintain consistent moisture during germination. Open the dome BRIEFLY once per day to allow fresh air in and reduce mold risk. Remove the dome entirely once seedlings emerge.
Post-Germination Care
• Provide strong light and good airflow to prevent damping off
• Water from the base or mist to avoid disturbing roots
• Once seedlings have 2–3 true leaves, transplant into individual pots
• Harden off before transplanting outdoors
Growing Tips
• Plant in well-drained, alkaline to neutral soil
• Prefers full sun, though light afternoon shade is tolerated in hot climates
• Excellent in rock gardens, borders, and cascading over walls
• Drought-tolerant once established
• Avoid overwatering — good drainage is essential to prevent root rot
Winter Notes
• Hardy perennial, USDA zones 4–9
• Can overwinter in trays or pots outdoors in protected areas after hardening off
More guides at: bloomoutlet.com/seed-guides