Tall cottage-garden biennial or short-lived perennial with broad funnel flowers in pink, white, yellow, or the dark-purple "black" form. The black flowers produce a deep violet to near-black natural dye.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 3–8 | −40 °C to −6.7 °C | Plant tolerates down to this zone |
| RHS hardiness rating | H7 | down to −20 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 3–8 | −34 °C to −1 °C | Plant tolerates down to this zone |
| Australian (ANBG) zone | Zone 1–6 | −15 °C to 15 °C | Plant tolerates down to this zone |
Growing notes
- Dark-purple to near-black dye extracted from the deep "black" flowers of the cultivar Alcea rosea var. nigra — gives a rare deep violet to near-black on wool with iron mordant
- Pale-flowered forms produce only weak unfixed dyes — for dye use, plant the dark cultivars specifically
- Strictly biennial in habit — sow successive years, or allow self-seeding to perpetuate
- Rust disease is the main pest — accept some leaf damage or replace plantings every 2–3 years
Categories
Related plants
Cross-check Hollyhock against your zones