Silver Thistle

Weather Thistle (Silver thistle) - Carlina acaulis ssp. simplex.
Origin: Southern and Eastern Europe.
Large, shiny white flowering blooms with silvery foliage.
History: The Genus comes from Charles (Carolus). According to medieval folklore, Charlemagne, or Charles the Great, used this root to cure the ills of his troops.
Short-stemmed, pure white blossoms with silver bracts when mature. Open on dry days, and closed in the evenings and rainy days.
Natural Flowering Period: July - September
Winter Hardiness Zones: Z3-9.
Growth Habit: low-growing rosettes.
Foliage: Deeply dissected leaves with hairy undersides
Height with Flowers: 50 cm
Spacing between Plants: 40 cm.
Soil Requirements: dry, well-drained, infertile soils, pH 6.5 - 7.5.
Location: full sun.
Use: plant in the rock garden or mixed containers with Allium senescens, Coreopsis auriculata "Elfin Gold" and Dracocephalum argunense "Fuji Blue".
Specialities: cut flower candidate and medicinal potential.
1,0 g = 250 seeds.

Germination: these plant seeds germinate rapidly depending on species and origin. If germination does not occur after 3-4 weeks a cooling period of 2-4 weeks is recommended.
Best Sowing Dates: November - March
Sowing to Germination: 5 - 8 weeks
Germination to Transplant: 3 - 4 weeks
Transplanting to Salable Plant: 6 - 8 weeks.
Forcing: an obvious place to experiment - following vernalization - would be raising daytime temperatures to +15° +17°C. Provide 16 hours of continuous lighting. During the short days of winter, provide a night interruption lighting of 4 hours between 10:00 p.m. and 2:00 a.m.

Weather Thistle. Bot. syn.: Carlina acaulis var. caulescens.